Abstract

We implement an ultrafast pulsed type-II parametric down conversion source in a periodically poled KTP waveguide at telecommunication wavelengths with almost identical properties between signal and idler. As such, our source resembles closely a pure, genuine single mode photon pair source with indistinguishable modes. We measure the joint spectral intensity distribution and second order correlation functions of the marginal beams and find with both methods very low effective mode numbers corresponding to a Schmidt number below 1.16. We further demonstrate the indistinguishability as well as the purity of signal and idler photons by Hong-Ou-Mandel interferences between signal and idler and between signal/idler and a coherent field, respectively. Without using narrowband spectral filtering, we achieve a visibility for the interference between signal and idler of 94.8% and determine a purity of more than 80% for the heralded single photon states. Moreover, we measure raw heralding efficiencies of 20.5% and 15.5% for the signal and idler beams corresponding to detector-loss corrected values of 80% and 70%.

© 2013 OSA

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  5. A. B. U’Ren, C. Silberhorn, K. Banaszek, and I. A. Walmsley, “Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks,” Phys. Rev. Lett. 93, 093601 (2004).
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    [Crossref]
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  33. R. J. Glauber, “The quantum theory of optical coherence,” Phys. Rev. 130, 2529–2539 (1963).
    [Crossref]
  34. A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
    [Crossref]
  35. A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background,” Phys. Status Solidi 8, 1216–1219 (2011).
    [Crossref]
  36. D. N. Klyshko, “Utilization of vacuum fluctuations as an optical brightness standard,” Sov. J. Quantum Electron. 7, 591–595 (1977).
    [Crossref]
  37. J. G. Rarity, K. D. Ridley, and P. R. Tapster, “Absolute measurement of detector quantum efficiency using parametric downconversion,” Appl. Opt. 26, 4616–4619 (1987).
    [Crossref] [PubMed]
  38. D. Achilles, C. Silberhorn, and I. A. Walmsley, “Direct, loss-tolerant characterization of nonclassical photon statistics,” Phys. Rev. Lett. 97, 043602 (2006).
    [Crossref] [PubMed]
  39. M. Avenhaus, A. Eckstein, P. J. Mosley, and C. Silberhorn, “Fiber-assisted single-photon spectrograph,” Opt. Lett. 34, 2873 (2009).
    [Crossref] [PubMed]
  40. B. Brecht and C. Silberhorn, “Characterizing entanglement in pulsed parametric down-conversion using chrono-cyclic wigner functions,” Phys. Rev. A 87, 053810 (2013).
    [Crossref]
  41. X. Li, L. Yang, L. Cui, Z. Y. Ou, and D. Yu, “Fiber-based source of photon pairs at telecom band with high temporal coherence and brightness for quantum information processing,” Opt. Lett. 33, 593 (2008).
    [Crossref] [PubMed]
  42. H. Takesue and B. Miquel, “Entanglement swapping using telecom-band photons generated in fibers,” Opt. Express 17, 10748–10756 (2009).
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  43. R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
    [Crossref]

2013 (1)

B. Brecht and C. Silberhorn, “Characterizing entanglement in pulsed parametric down-conversion using chrono-cyclic wigner functions,” Phys. Rev. A 87, 053810 (2013).
[Crossref]

2012 (3)

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

M. Tanida, R. Okamoto, and S. Takeuchi, “Highly indistinguishable heralded single-photon sources using parametric down conversion,” Opt. Express 20, 15275 (2012).
[Crossref] [PubMed]

2011 (5)

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Highly efficient single-pass source of pulsed single-mode twin beams of light,” Phys. Rev. Lett. 106, 013603 (2011).
[Crossref] [PubMed]

T. Gerrits, M. J. Stevens, B. Baek, B. Calkins, A. Lita, S. Glancy, E. Knill, S. W. Nam, R. P. Mirin, R. H. Hadfield, R. S. Bennink, W. P. Grice, S. Dorenbos, T. Zijlstra, T. Klapwijk, and V. Zwiller, “Generation of degenerate, factorizable, pulsed squeezed light at telecom wavelengths,” Opt. Express 19, 24434–24447 (2011).
[Crossref] [PubMed]

A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
[Crossref]

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background,” Phys. Status Solidi 8, 1216–1219 (2011).
[Crossref]

R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

2010 (3)

K. N. Cassemiro, K. Laiho, and C. Silberhorn, “Accessing the purity of a single photon by the width of the HongOuMandel interference,” New J. Phys. 12, 113052 (2010).
[Crossref]

E. Bimbard, N. Jain, A. MacRae, and A. I. Lvovsky, “Quantum-optical state engineering up to the two-photon level,” Nature Photon. 4, 243–247 (2010).
[Crossref]

A. M. Brańczyk, T. C. Ralph, W. Helwig, and C. Silberhorn, “Optimized generation of heralded fock states using parametric down-conversion,” New J. Phys. 12, 063001 (2010).
[Crossref]

2009 (7)

K. Laiho, K. N. Cassemiro, and C. Silberhorn, “Producing high fidelity single photons with optimal brightness via waveguided parametric down-conversion,” Opt. Express 17, 22823–22837 (2009).
[Crossref]

P. Kolenderski and W. Wasilewski, “Derivation of the density matrix of a single photon produced in parametric down-conversion,” Phys. Rev. A 80, 015801 (2009).
[Crossref]

M. Avenhaus, A. Eckstein, P. J. Mosley, and C. Silberhorn, “Fiber-assisted single-photon spectrograph,” Opt. Lett. 34, 2873 (2009).
[Crossref] [PubMed]

F. W. Sun and C. W. Wong, “Indistinguishability of independent single photons,” Phys. Rev. A 79, 013824 (2009).
[Crossref]

M. Avenhaus, M. V. Chekhova, L. A. Krivitsky, G. Leuchs, and C. Silberhorn, “Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion,” Phys. Rev. A 79, 043836 (2009).
[Crossref]

O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
[Crossref] [PubMed]

H. Takesue and B. Miquel, “Entanglement swapping using telecom-band photons generated in fibers,” Opt. Express 17, 10748–10756 (2009).
[Crossref] [PubMed]

2008 (3)

X. Li, L. Yang, L. Cui, Z. Y. Ou, and D. Yu, “Fiber-based source of photon pairs at telecom band with high temporal coherence and brightness for quantum information processing,” Opt. Lett. 33, 593 (2008).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, and I. A. Walmsley, “Conditional preparation of single photons using parametric downconversion: a recipe for purity,” New J. Phys. 10, 093011 (2008).
[Crossref]

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

2007 (3)

P. P. Rohde, W. Mauerer, and C. Silberhorn, “Spectral structure and decompositions of optical states, and their applications,” New J. Phys. 9, 91 (2007).
[Crossref]

K. Wakui, H. Takahashi, A. Furusawa, and M. Sasaki, “Photon subtracted squeezed states generated with periodically poled KTiOPO4,” Opt. Express 15, 3568–3574 (2007).
[Crossref] [PubMed]

W. Wasilewski, P. Kolenderski, and R. Frankowski, “Spectral density matrix of a single photon measured,” Phys. Rev. Lett. 99, 123601 (2007).
[Crossref] [PubMed]

2006 (2)

D. Achilles, C. Silberhorn, and I. A. Walmsley, “Direct, loss-tolerant characterization of nonclassical photon statistics,” Phys. Rev. Lett. 97, 043602 (2006).
[Crossref] [PubMed]

T. C. Ralph, “Quantum optical systems for the implementation of quantum information processing,” Rep. Prog. Phys. 69, 853–898 (2006).
[Crossref]

2005 (2)

T. Pittman, B. Jacobs, and J. Franson, “Heralding single photons from pulsed parametric down-conversion,” Optics Communications 246, 545–550 (2005).
[Crossref]

A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

2004 (2)

A. Zavatta, S. Viciani, and M. Bellini, “Quantum-to-classical transition with single-photon-added coherent states of light,” Science 306, 660–662 (2004).
[Crossref] [PubMed]

A. B. U’Ren, C. Silberhorn, K. Banaszek, and I. A. Walmsley, “Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks,” Phys. Rev. Lett. 93, 093601 (2004).
[Crossref]

2003 (1)

T. B. Pittman and J. D. Franson, “Violation of bells inequality with photons from independent sources,” Phys. Rev. Lett. 90, 240401 (2003).
[Crossref] [PubMed]

2001 (3)

W. P. Grice, A. B. U’Ren, and I. A. Walmsley, “Eliminating frequency and space-time correlations in multiphoton states,” Phys. Rev. A 64, 063815 (2001).
[Crossref]

E. Knill, R. Laflamme, and G. J. Milburn, “A scheme for efficient quantum computation with linear optics,” Nature 409, 46–52 (2001).
[Crossref] [PubMed]

A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, and S. Schiller, “Quantum state reconstruction of the single-photon fock state,” Phys. Rev. Lett. 87, 050402 (2001).
[Crossref] [PubMed]

2000 (1)

C. K. Law, I. A. Walmsley, and J. H. Eberly, “Continuous frequency entanglement: Effective finite hilbert space and entropy control,” Phys. Rev. Lett. 84, 5304–5307 (2000).
[Crossref] [PubMed]

1998 (1)

P. R. Tapster and J. G. Rarity, “Photon statistics of pulsed parametric light,” J. Mod. Opt. 45, 595–604 (1998).
[Crossref]

1987 (2)

C. K. Hong, Z. Y. Ou, and L. Mandel, “Measurement of subpicosecond time intervals between two photons by interference,” Phys. Rev. Lett. 59, 2044–2046 (1987).
[Crossref] [PubMed]

J. G. Rarity, K. D. Ridley, and P. R. Tapster, “Absolute measurement of detector quantum efficiency using parametric downconversion,” Appl. Opt. 26, 4616–4619 (1987).
[Crossref] [PubMed]

1977 (1)

D. N. Klyshko, “Utilization of vacuum fluctuations as an optical brightness standard,” Sov. J. Quantum Electron. 7, 591–595 (1977).
[Crossref]

1963 (1)

R. J. Glauber, “The quantum theory of optical coherence,” Phys. Rev. 130, 2529–2539 (1963).
[Crossref]

Aaronson, S.

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

Achilles, D.

D. Achilles, C. Silberhorn, and I. A. Walmsley, “Direct, loss-tolerant characterization of nonclassical photon statistics,” Phys. Rev. Lett. 97, 043602 (2006).
[Crossref] [PubMed]

Aichele, T.

A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, and S. Schiller, “Quantum state reconstruction of the single-photon fock state,” Phys. Rev. Lett. 87, 050402 (2001).
[Crossref] [PubMed]

Avenhaus, M.

M. Avenhaus, M. V. Chekhova, L. A. Krivitsky, G. Leuchs, and C. Silberhorn, “Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion,” Phys. Rev. A 79, 043836 (2009).
[Crossref]

M. Avenhaus, A. Eckstein, P. J. Mosley, and C. Silberhorn, “Fiber-assisted single-photon spectrograph,” Opt. Lett. 34, 2873 (2009).
[Crossref] [PubMed]

Baek, B.

Banaszek, K.

A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

A. B. U’Ren, C. Silberhorn, K. Banaszek, and I. A. Walmsley, “Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks,” Phys. Rev. Lett. 93, 093601 (2004).
[Crossref]

Barbieri, M.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Bellini, M.

A. Zavatta, S. Viciani, and M. Bellini, “Quantum-to-classical transition with single-photon-added coherent states of light,” Science 306, 660–662 (2004).
[Crossref] [PubMed]

Bennink, R. S.

Benson, O.

A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, and S. Schiller, “Quantum state reconstruction of the single-photon fock state,” Phys. Rev. Lett. 87, 050402 (2001).
[Crossref] [PubMed]

Bimbard, E.

E. Bimbard, N. Jain, A. MacRae, and A. I. Lvovsky, “Quantum-optical state engineering up to the two-photon level,” Nature Photon. 4, 243–247 (2010).
[Crossref]

Booth, M. J.

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Branczyk, A. M.

A. M. Brańczyk, T. C. Ralph, W. Helwig, and C. Silberhorn, “Optimized generation of heralded fock states using parametric down-conversion,” New J. Phys. 12, 063001 (2010).
[Crossref]

Brecht, B.

B. Brecht and C. Silberhorn, “Characterizing entanglement in pulsed parametric down-conversion using chrono-cyclic wigner functions,” Phys. Rev. A 87, 053810 (2013).
[Crossref]

Broome, M. A.

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

Calkins, B.

Cassemiro, K. N.

A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
[Crossref]

K. N. Cassemiro, K. Laiho, and C. Silberhorn, “Accessing the purity of a single photon by the width of the HongOuMandel interference,” New J. Phys. 12, 113052 (2010).
[Crossref]

K. Laiho, K. N. Cassemiro, and C. Silberhorn, “Producing high fidelity single photons with optimal brightness via waveguided parametric down-conversion,” Opt. Express 17, 22823–22837 (2009).
[Crossref]

Chekhova, M. V.

M. Avenhaus, M. V. Chekhova, L. A. Krivitsky, G. Leuchs, and C. Silberhorn, “Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion,” Phys. Rev. A 79, 043836 (2009).
[Crossref]

Christ, A.

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Highly efficient single-pass source of pulsed single-mode twin beams of light,” Phys. Rev. Lett. 106, 013603 (2011).
[Crossref] [PubMed]

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background,” Phys. Status Solidi 8, 1216–1219 (2011).
[Crossref]

A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
[Crossref]

Cohen, O.

O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
[Crossref] [PubMed]

Cui, L.

Datta, A.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

Dorenbos, S.

Dove, J.

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

Eberly, J. H.

C. K. Law, I. A. Walmsley, and J. H. Eberly, “Continuous frequency entanglement: Effective finite hilbert space and entropy control,” Phys. Rev. Lett. 84, 5304–5307 (2000).
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Eckstein, A.

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Highly efficient single-pass source of pulsed single-mode twin beams of light,” Phys. Rev. Lett. 106, 013603 (2011).
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A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background,” Phys. Status Solidi 8, 1216–1219 (2011).
[Crossref]

A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
[Crossref]

M. Avenhaus, A. Eckstein, P. J. Mosley, and C. Silberhorn, “Fiber-assisted single-photon spectrograph,” Opt. Lett. 34, 2873 (2009).
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R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Erdmann, R.

A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

Fedrizzi, A.

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

Frankowski, R.

W. Wasilewski, P. Kolenderski, and R. Frankowski, “Spectral density matrix of a single photon measured,” Phys. Rev. Lett. 99, 123601 (2007).
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T. Pittman, B. Jacobs, and J. Franson, “Heralding single photons from pulsed parametric down-conversion,” Optics Communications 246, 545–550 (2005).
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T. B. Pittman and J. D. Franson, “Violation of bells inequality with photons from independent sources,” Phys. Rev. Lett. 90, 240401 (2003).
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Gates, J. C.

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A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

W. P. Grice, A. B. U’Ren, and I. A. Walmsley, “Eliminating frequency and space-time correlations in multiphoton states,” Phys. Rev. A 64, 063815 (2001).
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Hansen, H.

A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, and S. Schiller, “Quantum state reconstruction of the single-photon fock state,” Phys. Rev. Lett. 87, 050402 (2001).
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Helwig, W.

A. M. Brańczyk, T. C. Ralph, W. Helwig, and C. Silberhorn, “Optimized generation of heralded fock states using parametric down-conversion,” New J. Phys. 12, 063001 (2010).
[Crossref]

Hong, C. K.

C. K. Hong, Z. Y. Ou, and L. Mandel, “Measurement of subpicosecond time intervals between two photons by interference,” Phys. Rev. Lett. 59, 2044–2046 (1987).
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J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
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J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
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T. Pittman, B. Jacobs, and J. Franson, “Heralding single photons from pulsed parametric down-conversion,” Optics Communications 246, 545–550 (2005).
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E. Bimbard, N. Jain, A. MacRae, and A. I. Lvovsky, “Quantum-optical state engineering up to the two-photon level,” Nature Photon. 4, 243–247 (2010).
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Jin, R.-B.

R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Jin, X.-M.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
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J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
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Klyshko, D. N.

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Kolenderski, P.

P. Kolenderski and W. Wasilewski, “Derivation of the density matrix of a single photon produced in parametric down-conversion,” Phys. Rev. A 80, 015801 (2009).
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W. Wasilewski, P. Kolenderski, and R. Frankowski, “Spectral density matrix of a single photon measured,” Phys. Rev. Lett. 99, 123601 (2007).
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Kolthammer, W. S.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Kosaka, H.

R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Krivitsky, L. A.

M. Avenhaus, M. V. Chekhova, L. A. Krivitsky, G. Leuchs, and C. Silberhorn, “Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion,” Phys. Rev. A 79, 043836 (2009).
[Crossref]

Kundys, D.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

Laflamme, R.

E. Knill, R. Laflamme, and G. J. Milburn, “A scheme for efficient quantum computation with linear optics,” Nature 409, 46–52 (2001).
[Crossref] [PubMed]

Laiho, K.

A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
[Crossref]

K. N. Cassemiro, K. Laiho, and C. Silberhorn, “Accessing the purity of a single photon by the width of the HongOuMandel interference,” New J. Phys. 12, 113052 (2010).
[Crossref]

K. Laiho, K. N. Cassemiro, and C. Silberhorn, “Producing high fidelity single photons with optimal brightness via waveguided parametric down-conversion,” Opt. Express 17, 22823–22837 (2009).
[Crossref]

Langford, N. K.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Law, C. K.

C. K. Law, I. A. Walmsley, and J. H. Eberly, “Continuous frequency entanglement: Effective finite hilbert space and entropy control,” Phys. Rev. Lett. 84, 5304–5307 (2000).
[Crossref] [PubMed]

Leuchs, G.

M. Avenhaus, M. V. Chekhova, L. A. Krivitsky, G. Leuchs, and C. Silberhorn, “Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion,” Phys. Rev. A 79, 043836 (2009).
[Crossref]

Li, X.

Lita, A.

Lundeen, J. S.

O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, and I. A. Walmsley, “Conditional preparation of single photons using parametric downconversion: a recipe for purity,” New J. Phys. 10, 093011 (2008).
[Crossref]

Lvovsky, A. I.

E. Bimbard, N. Jain, A. MacRae, and A. I. Lvovsky, “Quantum-optical state engineering up to the two-photon level,” Nature Photon. 4, 243–247 (2010).
[Crossref]

A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, and S. Schiller, “Quantum state reconstruction of the single-photon fock state,” Phys. Rev. Lett. 87, 050402 (2001).
[Crossref] [PubMed]

MacRae, A.

E. Bimbard, N. Jain, A. MacRae, and A. I. Lvovsky, “Quantum-optical state engineering up to the two-photon level,” Nature Photon. 4, 243–247 (2010).
[Crossref]

Mandel, L.

C. K. Hong, Z. Y. Ou, and L. Mandel, “Measurement of subpicosecond time intervals between two photons by interference,” Phys. Rev. Lett. 59, 2044–2046 (1987).
[Crossref] [PubMed]

Matsuda, N.

R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Mauerer, W.

P. P. Rohde, W. Mauerer, and C. Silberhorn, “Spectral structure and decompositions of optical states, and their applications,” New J. Phys. 9, 91 (2007).
[Crossref]

Metcalf, B. J.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Milburn, G. J.

E. Knill, R. Laflamme, and G. J. Milburn, “A scheme for efficient quantum computation with linear optics,” Nature 409, 46–52 (2001).
[Crossref] [PubMed]

Miquel, B.

Mirin, R. P.

Mitsumori, Y.

R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Mlynek, J.

A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, and S. Schiller, “Quantum state reconstruction of the single-photon fock state,” Phys. Rev. Lett. 87, 050402 (2001).
[Crossref] [PubMed]

Moore, M.

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Mosley, P. J.

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Highly efficient single-pass source of pulsed single-mode twin beams of light,” Phys. Rev. Lett. 106, 013603 (2011).
[Crossref] [PubMed]

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background,” Phys. Status Solidi 8, 1216–1219 (2011).
[Crossref]

M. Avenhaus, A. Eckstein, P. J. Mosley, and C. Silberhorn, “Fiber-assisted single-photon spectrograph,” Opt. Lett. 34, 2873 (2009).
[Crossref] [PubMed]

O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, and I. A. Walmsley, “Conditional preparation of single photons using parametric downconversion: a recipe for purity,” New J. Phys. 10, 093011 (2008).
[Crossref]

Nam, S. W.

Okamoto, R.

Ou, Z. Y.

X. Li, L. Yang, L. Cui, Z. Y. Ou, and D. Yu, “Fiber-based source of photon pairs at telecom band with high temporal coherence and brightness for quantum information processing,” Opt. Lett. 33, 593 (2008).
[Crossref] [PubMed]

C. K. Hong, Z. Y. Ou, and L. Mandel, “Measurement of subpicosecond time intervals between two photons by interference,” Phys. Rev. Lett. 59, 2044–2046 (1987).
[Crossref] [PubMed]

Pittman, T.

T. Pittman, B. Jacobs, and J. Franson, “Heralding single photons from pulsed parametric down-conversion,” Optics Communications 246, 545–550 (2005).
[Crossref]

Pittman, T. B.

T. B. Pittman and J. D. Franson, “Violation of bells inequality with photons from independent sources,” Phys. Rev. Lett. 90, 240401 (2003).
[Crossref] [PubMed]

Puentes, G.

O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
[Crossref] [PubMed]

Rahimi-Keshari, S.

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

Ralph, T. C.

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

A. M. Brańczyk, T. C. Ralph, W. Helwig, and C. Silberhorn, “Optimized generation of heralded fock states using parametric down-conversion,” New J. Phys. 12, 063001 (2010).
[Crossref]

T. C. Ralph, “Quantum optical systems for the implementation of quantum information processing,” Rep. Prog. Phys. 69, 853–898 (2006).
[Crossref]

Rarity, J. G.

Raymer, M. G.

A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

Ridley, K. D.

Rohde, P. P.

P. P. Rohde, W. Mauerer, and C. Silberhorn, “Spectral structure and decompositions of optical states, and their applications,” New J. Phys. 9, 91 (2007).
[Crossref]

Salter, P. S.

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Sasaki, M.

Schiller, S.

A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, and S. Schiller, “Quantum state reconstruction of the single-photon fock state,” Phys. Rev. Lett. 87, 050402 (2001).
[Crossref] [PubMed]

Shimizu, R.

R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Silberhorn, C.

B. Brecht and C. Silberhorn, “Characterizing entanglement in pulsed parametric down-conversion using chrono-cyclic wigner functions,” Phys. Rev. A 87, 053810 (2013).
[Crossref]

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background,” Phys. Status Solidi 8, 1216–1219 (2011).
[Crossref]

A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
[Crossref]

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Highly efficient single-pass source of pulsed single-mode twin beams of light,” Phys. Rev. Lett. 106, 013603 (2011).
[Crossref] [PubMed]

A. M. Brańczyk, T. C. Ralph, W. Helwig, and C. Silberhorn, “Optimized generation of heralded fock states using parametric down-conversion,” New J. Phys. 12, 063001 (2010).
[Crossref]

K. N. Cassemiro, K. Laiho, and C. Silberhorn, “Accessing the purity of a single photon by the width of the HongOuMandel interference,” New J. Phys. 12, 113052 (2010).
[Crossref]

M. Avenhaus, M. V. Chekhova, L. A. Krivitsky, G. Leuchs, and C. Silberhorn, “Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion,” Phys. Rev. A 79, 043836 (2009).
[Crossref]

K. Laiho, K. N. Cassemiro, and C. Silberhorn, “Producing high fidelity single photons with optimal brightness via waveguided parametric down-conversion,” Opt. Express 17, 22823–22837 (2009).
[Crossref]

M. Avenhaus, A. Eckstein, P. J. Mosley, and C. Silberhorn, “Fiber-assisted single-photon spectrograph,” Opt. Lett. 34, 2873 (2009).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

P. P. Rohde, W. Mauerer, and C. Silberhorn, “Spectral structure and decompositions of optical states, and their applications,” New J. Phys. 9, 91 (2007).
[Crossref]

D. Achilles, C. Silberhorn, and I. A. Walmsley, “Direct, loss-tolerant characterization of nonclassical photon statistics,” Phys. Rev. Lett. 97, 043602 (2006).
[Crossref] [PubMed]

A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

A. B. U’Ren, C. Silberhorn, K. Banaszek, and I. A. Walmsley, “Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks,” Phys. Rev. Lett. 93, 093601 (2004).
[Crossref]

Smith, B. J.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, and I. A. Walmsley, “Conditional preparation of single photons using parametric downconversion: a recipe for purity,” New J. Phys. 10, 093011 (2008).
[Crossref]

Smith, P. G. R.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
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Spring, J. B.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Stevens, M. J.

Sun, F. W.

F. W. Sun and C. W. Wong, “Indistinguishability of independent single photons,” Phys. Rev. A 79, 013824 (2009).
[Crossref]

Takahashi, H.

Takesue, H.

Takeuchi, S.

Tanida, M.

Tapster, P. R.

Thomas-Peter, N.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

U’Ren, A. B.

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

A. B. U’Ren, C. Silberhorn, K. Banaszek, and I. A. Walmsley, “Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks,” Phys. Rev. Lett. 93, 093601 (2004).
[Crossref]

W. P. Grice, A. B. U’Ren, and I. A. Walmsley, “Eliminating frequency and space-time correlations in multiphoton states,” Phys. Rev. A 64, 063815 (2001).
[Crossref]

Viciani, S.

A. Zavatta, S. Viciani, and M. Bellini, “Quantum-to-classical transition with single-photon-added coherent states of light,” Science 306, 660–662 (2004).
[Crossref] [PubMed]

Wakui, K.

Walmsley, I. A.

J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
[Crossref] [PubMed]

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
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P. J. Mosley, J. S. Lundeen, B. J. Smith, and I. A. Walmsley, “Conditional preparation of single photons using parametric downconversion: a recipe for purity,” New J. Phys. 10, 093011 (2008).
[Crossref]

D. Achilles, C. Silberhorn, and I. A. Walmsley, “Direct, loss-tolerant characterization of nonclassical photon statistics,” Phys. Rev. Lett. 97, 043602 (2006).
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A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

A. B. U’Ren, C. Silberhorn, K. Banaszek, and I. A. Walmsley, “Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks,” Phys. Rev. Lett. 93, 093601 (2004).
[Crossref]

W. P. Grice, A. B. U’Ren, and I. A. Walmsley, “Eliminating frequency and space-time correlations in multiphoton states,” Phys. Rev. A 64, 063815 (2001).
[Crossref]

C. K. Law, I. A. Walmsley, and J. H. Eberly, “Continuous frequency entanglement: Effective finite hilbert space and entropy control,” Phys. Rev. Lett. 84, 5304–5307 (2000).
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J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

Wasilewski, W.

P. Kolenderski and W. Wasilewski, “Derivation of the density matrix of a single photon produced in parametric down-conversion,” Phys. Rev. A 80, 015801 (2009).
[Crossref]

W. Wasilewski, P. Kolenderski, and R. Frankowski, “Spectral density matrix of a single photon measured,” Phys. Rev. Lett. 99, 123601 (2007).
[Crossref] [PubMed]

Wasylczyk, P.

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

White, A. G.

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

Wong, C. W.

F. W. Sun and C. W. Wong, “Indistinguishability of independent single photons,” Phys. Rev. A 79, 013824 (2009).
[Crossref]

Yang, L.

Yu, D.

Zavatta, A.

A. Zavatta, S. Viciani, and M. Bellini, “Quantum-to-classical transition with single-photon-added coherent states of light,” Science 306, 660–662 (2004).
[Crossref] [PubMed]

Zhang, J.

R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Zijlstra, T.

Zwiller, V.

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A. B. U’Ren, C. Silberhorn, K. Banaszek, I. A. Walmsley, R. Erdmann, W. P. Grice, and M. G. Raymer, “Generation of pure-state single-photon wavepackets by conditional preparation based on spontaneous parametric downconversion,” Laser Phys. 15, 146 (2005).

Nature (1)

E. Knill, R. Laflamme, and G. J. Milburn, “A scheme for efficient quantum computation with linear optics,” Nature 409, 46–52 (2001).
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Nature Photon. (1)

E. Bimbard, N. Jain, A. MacRae, and A. I. Lvovsky, “Quantum-optical state engineering up to the two-photon level,” Nature Photon. 4, 243–247 (2010).
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New J. Phys. (5)

A. M. Brańczyk, T. C. Ralph, W. Helwig, and C. Silberhorn, “Optimized generation of heralded fock states using parametric down-conversion,” New J. Phys. 12, 063001 (2010).
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P. P. Rohde, W. Mauerer, and C. Silberhorn, “Spectral structure and decompositions of optical states, and their applications,” New J. Phys. 9, 91 (2007).
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K. N. Cassemiro, K. Laiho, and C. Silberhorn, “Accessing the purity of a single photon by the width of the HongOuMandel interference,” New J. Phys. 12, 113052 (2010).
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A. Christ, K. Laiho, A. Eckstein, K. N. Cassemiro, and C. Silberhorn, “Probing multimode squeezing with correlation functions,” New J. Phys. 13, 033027 (2011).
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P. J. Mosley, J. S. Lundeen, B. J. Smith, and I. A. Walmsley, “Conditional preparation of single photons using parametric downconversion: a recipe for purity,” New J. Phys. 10, 093011 (2008).
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Opt. Express (5)

Opt. Lett. (2)

Optics Communications (1)

T. Pittman, B. Jacobs, and J. Franson, “Heralding single photons from pulsed parametric down-conversion,” Optics Communications 246, 545–550 (2005).
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Phys. Rev. A (6)

P. Kolenderski and W. Wasilewski, “Derivation of the density matrix of a single photon produced in parametric down-conversion,” Phys. Rev. A 80, 015801 (2009).
[Crossref]

F. W. Sun and C. W. Wong, “Indistinguishability of independent single photons,” Phys. Rev. A 79, 013824 (2009).
[Crossref]

M. Avenhaus, M. V. Chekhova, L. A. Krivitsky, G. Leuchs, and C. Silberhorn, “Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion,” Phys. Rev. A 79, 043836 (2009).
[Crossref]

W. P. Grice, A. B. U’Ren, and I. A. Walmsley, “Eliminating frequency and space-time correlations in multiphoton states,” Phys. Rev. A 64, 063815 (2001).
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B. Brecht and C. Silberhorn, “Characterizing entanglement in pulsed parametric down-conversion using chrono-cyclic wigner functions,” Phys. Rev. A 87, 053810 (2013).
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R.-B. Jin, J. Zhang, R. Shimizu, N. Matsuda, Y. Mitsumori, H. Kosaka, and K. Edamatsu, “High-visibility non-classical interference between intrinsically pure heralded single photons and photons from a weak coherent field,” Phys. Rev. A 83, 031805 (2011).
[Crossref]

Phys. Rev. Lett. (10)

D. Achilles, C. Silberhorn, and I. A. Walmsley, “Direct, loss-tolerant characterization of nonclassical photon statistics,” Phys. Rev. Lett. 97, 043602 (2006).
[Crossref] [PubMed]

A. B. U’Ren, C. Silberhorn, K. Banaszek, and I. A. Walmsley, “Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks,” Phys. Rev. Lett. 93, 093601 (2004).
[Crossref]

P. J. Mosley, J. S. Lundeen, B. J. Smith, P. Wasylczyk, A. B. U’Ren, C. Silberhorn, and I. A. Walmsley, “Heralded generation of ultrafast single photons in pure quantum states,” Phys. Rev. Lett. 100, 133601 (2008).
[Crossref] [PubMed]

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Highly efficient single-pass source of pulsed single-mode twin beams of light,” Phys. Rev. Lett. 106, 013603 (2011).
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O. Cohen, J. S. Lundeen, B. J. Smith, G. Puentes, P. J. Mosley, and I. A. Walmsley, “Tailored photon-pair generation in optical fibers,” Phys. Rev. Lett. 102, 123603 (2009).
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W. Wasilewski, P. Kolenderski, and R. Frankowski, “Spectral density matrix of a single photon measured,” Phys. Rev. Lett. 99, 123601 (2007).
[Crossref] [PubMed]

C. K. Law, I. A. Walmsley, and J. H. Eberly, “Continuous frequency entanglement: Effective finite hilbert space and entropy control,” Phys. Rev. Lett. 84, 5304–5307 (2000).
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Phys. Status Solidi (1)

A. Eckstein, A. Christ, P. J. Mosley, and C. Silberhorn, “Realistic g(2) measurement of a PDC source with single photon detectors in the presence of background,” Phys. Status Solidi 8, 1216–1219 (2011).
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J. B. Spring, B. J. Metcalf, P. C. Humphreys, W. S. Kolthammer, X.-M. Jin, M. Barbieri, A. Datta, N. Thomas-Peter, N. K. Langford, D. Kundys, J. C. Gates, B. J. Smith, P. G. R. Smith, and I. A. Walmsley, “Boson sampling on a photonic chip,” Science 339, 798–801 (2012).
[Crossref] [PubMed]

M. A. Broome, A. Fedrizzi, S. Rahimi-Keshari, J. Dove, S. Aaronson, T. C. Ralph, and A. G. White, “Photonic boson sampling in a tunable circuit,” Science 339, 797–798 (2012).

A. Zavatta, S. Viciani, and M. Bellini, “Quantum-to-classical transition with single-photon-added coherent states of light,” Science 306, 660–662 (2004).
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A. Eckstein, “Mastering quantum light pulses with nonlinear waveguide interactions,” Ph.D. thesis, Naturwis-senschaftliche Fakultät der Friedrich-Alexander-Universität Erlangen-Nürnberg (2012).

J. B. Spring, P. S. Salter, B. J. Metcalf, P. C. Humphreys, M. Moore, N. Thomas-Peter, M. Barbieri, X.-M. Jin, N. K. Langford, W. S. Kolthammer, M. J. Booth, and I. A. Walmsley, “On-chip low loss heralded source of pure single photons,” Opt. Express21, 13522–13532 (2011) .
[Crossref]

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Figures (8)

Fig. 1
Fig. 1

Separable joint spectral amplitude resulting from a phasematching function ϕ with a positive slope multiplied by a pump function α of appropriate width.

Fig. 2
Fig. 2

The visibility of the HOM interference is proportional to the overlap (shaded area) of the JSA with itself under the exchange of signal and idler (contour plots). a) Positive correlation, K = 2 and visibility 70%. b) Decorrelation, K = 1 and visibility 96.7%. c) Negative correlation, K = 2 and visibility 99.8%. Panel b) corresponds to the situation presented in this paper.

Fig. 3
Fig. 3

Comparison of an uncorrelated PDC state (dotted black lines) to a correlated PDC state (green, purple or solid black lines). Left: JSA. Center: reduced density matrix of signal. Right: HOM dip between signal and reference. Both cases, correlated and uncorrelated, have the same marginal spectral widths. Nevertheless, the width of the HOM dip reveals the amount of correlations.

Fig. 4
Fig. 4

Scheme of the setup. Pulsed light at telecom wavelengths is generated in an Ti:Sapph pumped optical parametric oscillator (OPO) and frequency doubled by second harmonic generation (SHG). Part of the light is separated for later use as a reference field. The repetition rate is lowered by an acousto-optical modulator (AOM) to match the repetition rate of the gated APDs. The 4-f spectrometer tailors the spectral width of the pump beam to achieve spectral decorrelation. The PDC state is generated inside the periodically poled KTP waveguide. The pump is separated by a long pass filter (LPF). A bandpass filter (BPF) is used to suppress background outside the PDC spectrum. Finally signal and idler are separated at a polarizing beam splitter (PBS).

Fig. 5
Fig. 5

Scheme of different measurement settings. a) JSI measurement; b) g(2)(0) measurement; c) HOM interference between signal and idler; d) 2-fold or 3-fold HOM interference with a reference field. The Id Quantique detectors(1MHz) are used for the JSI measurement and the NuCrypt detectors (40MHz) for the rest.

Fig. 6
Fig. 6

a) Marginal idler spectra for the decorrelated case with and without the bandpass filter (BF). One can see that the spectral filter fits nicely the idler spectrum, touching it only slightly at the very edges. b) Signal and idler spectra with the bandpass filter. Bottom: Measured joint spectral intensity for anticorrelation (c) and decorrelation (d). The pump widths are 0.5nm and 2.1nm, respectively.

Fig. 7
Fig. 7

HOM interference between signal and idler.

Fig. 8
Fig. 8

two-fold (left) and three-fold (right) HOM interference between signal and reference.

Equations (4)

Equations on this page are rendered with MathJax. Learn more.

ω s + ω i = ω p , k s + k i + 2 π Λ = k p ,
f ( ω s , ω i ) = ϕ ( ω s , ω i ) α ( ω s , ω i )
p ( τ ) = 1 2 1 2 Re d ω s d ω i f * ( ω s , ω i ) f ( ω i , ω s ) e i τ ( ω s ω i ) .
δ 2 = 1 2 σ 2 2 + 1 2 σ β 2

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