Abstract

Integrated photonic circuits offer the possibility for complex quantum optical experiments in higher-dimensional photonic systems. However, the advantages of integration and scalability can only be fully utilized with the availability of a source for higher-dimensional entangled photons. Here, a novel fiber integrated source for path-entangled photons in the telecom band at 1.55µm using only standard fiber technology is presented. Due to the special design the source shows good scalability towards higher-dimensional entangled photonic states (quNits), while path entanglement offers direct compatibility with on-chip path encoding. We present an experimental realization of a path-entangled two-qubit source. A very high quality of entanglement is verified by various measurements, i.a. a tomographic state reconstruction is performed leading to a background corrected fidelity of (99.45±0.06)%. Moreover, we describe an easy method for extending our source to arbitrarily high dimensions.

© 2012 OSA

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2011 (2)

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

X. Ma, S. Zotter, J. Kofler, T. Jennewein, and A. Zeilinger, “Experimental generation of single photons via active multiplexing,” Phys. Rev. A 83(4), 043814 (2011).
[CrossRef]

2010 (5)

A. Cabello, “Proposal for revealing quantum nonlocality via local contextuality,” Phys. Rev. Lett. 104(22), 220401 (2010).
[CrossRef] [PubMed]

T. Durt, B.-G. Englert, I. Bengtsson, and K. Życzkowski, “On mutually unbiased bases,” Int. J. Quantum Inf. 8(04), 535–640 (2010).
[CrossRef]

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

M. F. Saleh, G. Di Giuseppe, B. E. A. Saleh, and M. C. Teich, “Modal and polarization qubits in Ti:LiNbO3 photonic circuits for a universal quantum logic gate,” Opt. Express 18(19), 20475–20490 (2010).
[CrossRef] [PubMed]

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

2009 (4)

Y. Bromberg, Y. Lahini, R. Morandotti, and Y. Silberberg, “Quantum and classical correlations in waveguide lattices,” Phys. Rev. Lett. 102(25), 253904 (2009).
[CrossRef] [PubMed]

B. J. Smith, D. Kundys, N. Thomas-Peter, P. G. R. Smith, and I. A. Walmsley, “Phase-controlled integrated photonic quantum circuits,” Opt. Express 17(16), 13516–13525 (2009).
[CrossRef] [PubMed]

Z. Liu and H. Fan, “Decay of multiqudit entanglement,” Phys. Rev. A 79(6), 064305 (2009).
[CrossRef]

A. Rossi, G. Vallone, A. Chiuri, F. De Martini, and P. Mataloni, “Multipath entanglement of two photons,” Phys. Rev. Lett. 102(15), 153902 (2009).
[CrossRef] [PubMed]

2008 (2)

Q. Zhang, C. Langrock, H. Takesue, X. Xie, M. Fejer, and Y. Yamamoto, “Generation of 10-GHz clock sequential time-bin entanglement,” Opt. Express 16(5), 3293–3298 (2008).
[CrossRef] [PubMed]

A. Politi, M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-silicon waveguide quantum circuits,” Science 320(5876), 646–649 (2008).
[CrossRef] [PubMed]

2007 (2)

2005 (2)

X. Li, P. L. Voss, J. E. Sharping, and P. Kumar, “Optical-fiber source of polarization-entangled photons in the 1550 nm telecom band,” Phys. Rev. Lett. 94(5), 053601 (2005).
[CrossRef] [PubMed]

Y. L. Lim and A. Beige, “Multiphoton entanglement through a Bell multiport beam splitter,” Phys. Rev. A 71(6), 062311 (2005).
[CrossRef]

2004 (1)

M. Mohseni, A. M. Steinberg, and J. A. Bergou, “Optical realization of optimal unambiguous discrimination for pure and mixed quantum states,” Phys. Rev. Lett. 93(20), 200403 (2004).
[CrossRef] [PubMed]

2003 (1)

G. J. Pryde and A. G. White, “Creation of maximally entangled photon-number states using optical fiber multiports,” Phys. Rev. A 68(5), 052315 (2003).
[CrossRef]

2002 (1)

N. J. Cerf, M. Bourennane, A. Karlsson, and N. Gisin, “Security of quantum key distribution using d-level systems,” Phys. Rev. Lett. 88(12), 127902 (2002).
[CrossRef] [PubMed]

2001 (2)

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

D. F. V. James, P. G. Kwiat, W. J. Munro, and A. G. White, “Measurement of qubits,” Phys. Rev. A 64(5), 052312 (2001).
[CrossRef]

1997 (1)

M. Zukowski, A. Zeilinger, and M. A. Horne, “Realizable higher-dimensional two-particle entanglements via multiport beam splitters,” Phys. Rev. A 55(4), 2564–2579 (1997).
[CrossRef]

1996 (2)

K. Mattle, H. Weinfurter, P. G. Kwiat, and A. Zeilinger, “Dense coding in experimental quantum communication,” Phys. Rev. Lett. 76(25), 4656–4659 (1996).
[CrossRef] [PubMed]

G. Weihs, M. Reck, H. Weinfurter, and A. Zeilinger, “Two-photon interference in optical fiber multiports,” Phys. Rev. A 54(1), 893–897 (1996).
[CrossRef] [PubMed]

1994 (1)

M. Reck, A. Zeilinger, H. J. Bernstein, and P. Bertani, “Experimental realization of any discrete unitary operator,” Phys. Rev. Lett. 73(1), 58–61 (1994).
[CrossRef] [PubMed]

1990 (1)

J. G. Rarity and P. R. Tapster, “Experimental violation of Bell’s inequality based on phase and momentum,” Phys. Rev. Lett. 64(21), 2495–2498 (1990).
[CrossRef] [PubMed]

1989 (1)

M. A. Horne, A. Shimony, and A. Zeilinger, “Two-particle interferometry,” Phys. Rev. Lett. 62(19), 2209–2212 (1989).
[CrossRef] [PubMed]

1983 (1)

P. Heywood and M. L. G. Redhead, “Nonlocality and the Kochen-Specker paradox,” Found. Phys. 13(5), 481–499 (1983).
[CrossRef]

1969 (1)

J. F. Clauser, M. A. Horne, A. Shimony, and R. A. Holt, “Proposed experiment to test local hidden-variable theories,” Phys. Rev. Lett. 23(15), 880–884 (1969).
[CrossRef]

Baldi, P.

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Battle, P.

Beausoleil, R. G.

Beige, A.

Y. L. Lim and A. Beige, “Multiphoton entanglement through a Bell multiport beam splitter,” Phys. Rev. A 71(6), 062311 (2005).
[CrossRef]

Bengtsson, I.

T. Durt, B.-G. Englert, I. Bengtsson, and K. Życzkowski, “On mutually unbiased bases,” Int. J. Quantum Inf. 8(04), 535–640 (2010).
[CrossRef]

Bergou, J. A.

M. Mohseni, A. M. Steinberg, and J. A. Bergou, “Optical realization of optimal unambiguous discrimination for pure and mixed quantum states,” Phys. Rev. Lett. 93(20), 200403 (2004).
[CrossRef] [PubMed]

Bernstein, H. J.

M. Reck, A. Zeilinger, H. J. Bernstein, and P. Bertani, “Experimental realization of any discrete unitary operator,” Phys. Rev. Lett. 73(1), 58–61 (1994).
[CrossRef] [PubMed]

Bertani, P.

M. Reck, A. Zeilinger, H. J. Bernstein, and P. Bertani, “Experimental realization of any discrete unitary operator,” Phys. Rev. Lett. 73(1), 58–61 (1994).
[CrossRef] [PubMed]

Bourennane, M.

N. J. Cerf, M. Bourennane, A. Karlsson, and N. Gisin, “Security of quantum key distribution using d-level systems,” Phys. Rev. Lett. 88(12), 127902 (2002).
[CrossRef] [PubMed]

Bromberg, Y.

Y. Bromberg, Y. Lahini, R. Morandotti, and Y. Silberberg, “Quantum and classical correlations in waveguide lattices,” Phys. Rev. Lett. 102(25), 253904 (2009).
[CrossRef] [PubMed]

Cabello, A.

A. Cabello, “Proposal for revealing quantum nonlocality via local contextuality,” Phys. Rev. Lett. 104(22), 220401 (2010).
[CrossRef] [PubMed]

Cerf, N. J.

N. J. Cerf, M. Bourennane, A. Karlsson, and N. Gisin, “Security of quantum key distribution using d-level systems,” Phys. Rev. Lett. 88(12), 127902 (2002).
[CrossRef] [PubMed]

Chiuri, A.

A. Rossi, G. Vallone, A. Chiuri, F. De Martini, and P. Mataloni, “Multipath entanglement of two photons,” Phys. Rev. Lett. 102(15), 153902 (2009).
[CrossRef] [PubMed]

Clauser, J. F.

J. F. Clauser, M. A. Horne, A. Shimony, and R. A. Holt, “Proposed experiment to test local hidden-variable theories,” Phys. Rev. Lett. 23(15), 880–884 (1969).
[CrossRef]

Crespi, A.

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

Cryan, M. J.

A. Politi, M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-silicon waveguide quantum circuits,” Science 320(5876), 646–649 (2008).
[CrossRef] [PubMed]

De Martini, F.

A. Rossi, G. Vallone, A. Chiuri, F. De Martini, and P. Mataloni, “Multipath entanglement of two photons,” Phys. Rev. Lett. 102(15), 153902 (2009).
[CrossRef] [PubMed]

De Micheli, M.

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

De Riedmatten, H.

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Di Giuseppe, G.

Dreisow, F.

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

Durt, T.

T. Durt, B.-G. Englert, I. Bengtsson, and K. Życzkowski, “On mutually unbiased bases,” Int. J. Quantum Inf. 8(04), 535–640 (2010).
[CrossRef]

Englert, B.-G.

T. Durt, B.-G. Englert, I. Bengtsson, and K. Życzkowski, “On mutually unbiased bases,” Int. J. Quantum Inf. 8(04), 535–640 (2010).
[CrossRef]

Fan, H.

Z. Liu and H. Fan, “Decay of multiqudit entanglement,” Phys. Rev. A 79(6), 064305 (2009).
[CrossRef]

Fejer, M.

Fiorentino, M.

Gisin, N.

N. J. Cerf, M. Bourennane, A. Karlsson, and N. Gisin, “Security of quantum key distribution using d-level systems,” Phys. Rev. Lett. 88(12), 127902 (2002).
[CrossRef] [PubMed]

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Heinrich, M.

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

Heywood, P.

P. Heywood and M. L. G. Redhead, “Nonlocality and the Kochen-Specker paradox,” Found. Phys. 13(5), 481–499 (1983).
[CrossRef]

Holt, R. A.

J. F. Clauser, M. A. Horne, A. Shimony, and R. A. Holt, “Proposed experiment to test local hidden-variable theories,” Phys. Rev. Lett. 23(15), 880–884 (1969).
[CrossRef]

Horne, M. A.

M. Zukowski, A. Zeilinger, and M. A. Horne, “Realizable higher-dimensional two-particle entanglements via multiport beam splitters,” Phys. Rev. A 55(4), 2564–2579 (1997).
[CrossRef]

M. A. Horne, A. Shimony, and A. Zeilinger, “Two-particle interferometry,” Phys. Rev. Lett. 62(19), 2209–2212 (1989).
[CrossRef] [PubMed]

J. F. Clauser, M. A. Horne, A. Shimony, and R. A. Holt, “Proposed experiment to test local hidden-variable theories,” Phys. Rev. Lett. 23(15), 880–884 (1969).
[CrossRef]

James, D. F. V.

D. F. V. James, P. G. Kwiat, W. J. Munro, and A. G. White, “Measurement of qubits,” Phys. Rev. A 64(5), 052312 (2001).
[CrossRef]

Jennewein, T.

X. Ma, S. Zotter, J. Kofler, T. Jennewein, and A. Zeilinger, “Experimental generation of single photons via active multiplexing,” Phys. Rev. A 83(4), 043814 (2011).
[CrossRef]

Karlsson, A.

N. J. Cerf, M. Bourennane, A. Karlsson, and N. Gisin, “Security of quantum key distribution using d-level systems,” Phys. Rev. Lett. 88(12), 127902 (2002).
[CrossRef] [PubMed]

Keil, R.

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

Kofler, J.

X. Ma, S. Zotter, J. Kofler, T. Jennewein, and A. Zeilinger, “Experimental generation of single photons via active multiplexing,” Phys. Rev. A 83(4), 043814 (2011).
[CrossRef]

Kumar, P.

X. Li, P. L. Voss, J. E. Sharping, and P. Kumar, “Optical-fiber source of polarization-entangled photons in the 1550 nm telecom band,” Phys. Rev. Lett. 94(5), 053601 (2005).
[CrossRef] [PubMed]

Kundys, D.

Kwiat, P. G.

D. F. V. James, P. G. Kwiat, W. J. Munro, and A. G. White, “Measurement of qubits,” Phys. Rev. A 64(5), 052312 (2001).
[CrossRef]

K. Mattle, H. Weinfurter, P. G. Kwiat, and A. Zeilinger, “Dense coding in experimental quantum communication,” Phys. Rev. Lett. 76(25), 4656–4659 (1996).
[CrossRef] [PubMed]

Lahini, Y.

Y. Bromberg, Y. Lahini, R. Morandotti, and Y. Silberberg, “Quantum and classical correlations in waveguide lattices,” Phys. Rev. Lett. 102(25), 253904 (2009).
[CrossRef] [PubMed]

Laing, A.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Langrock, C.

Li, X.

X. Li, P. L. Voss, J. E. Sharping, and P. Kumar, “Optical-fiber source of polarization-entangled photons in the 1550 nm telecom band,” Phys. Rev. Lett. 94(5), 053601 (2005).
[CrossRef] [PubMed]

Lim, Y. L.

Y. L. Lim and A. Beige, “Multiphoton entanglement through a Bell multiport beam splitter,” Phys. Rev. A 71(6), 062311 (2005).
[CrossRef]

Liu, Z.

Z. Liu and H. Fan, “Decay of multiqudit entanglement,” Phys. Rev. A 79(6), 064305 (2009).
[CrossRef]

Lobino, M.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Ma, X.

X. Ma, S. Zotter, J. Kofler, T. Jennewein, and A. Zeilinger, “Experimental generation of single photons via active multiplexing,” Phys. Rev. A 83(4), 043814 (2011).
[CrossRef]

Mataloni, P.

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

A. Rossi, G. Vallone, A. Chiuri, F. De Martini, and P. Mataloni, “Multipath entanglement of two photons,” Phys. Rev. Lett. 102(15), 153902 (2009).
[CrossRef] [PubMed]

Matthews, J. C. F.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Mattle, K.

K. Mattle, H. Weinfurter, P. G. Kwiat, and A. Zeilinger, “Dense coding in experimental quantum communication,” Phys. Rev. Lett. 76(25), 4656–4659 (1996).
[CrossRef] [PubMed]

Mohseni, M.

M. Mohseni, A. M. Steinberg, and J. A. Bergou, “Optical realization of optimal unambiguous discrimination for pure and mixed quantum states,” Phys. Rev. Lett. 93(20), 200403 (2004).
[CrossRef] [PubMed]

Morandotti, R.

Y. Bromberg, Y. Lahini, R. Morandotti, and Y. Silberberg, “Quantum and classical correlations in waveguide lattices,” Phys. Rev. Lett. 102(25), 253904 (2009).
[CrossRef] [PubMed]

Munro, M. W.

Munro, W. J.

D. F. V. James, P. G. Kwiat, W. J. Munro, and A. G. White, “Measurement of qubits,” Phys. Rev. A 64(5), 052312 (2001).
[CrossRef]

Nolte, S.

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

O’Brien, J. L.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

A. Politi, M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-silicon waveguide quantum circuits,” Science 320(5876), 646–649 (2008).
[CrossRef] [PubMed]

Osellame, R.

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

Ostrowsky, D. B.

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Peruzzo, A.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Politi, A.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

A. Politi, M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-silicon waveguide quantum circuits,” Science 320(5876), 646–649 (2008).
[CrossRef] [PubMed]

Pryde, G. J.

G. J. Pryde and A. G. White, “Creation of maximally entangled photon-number states using optical fiber multiports,” Phys. Rev. A 68(5), 052315 (2003).
[CrossRef]

Ramponi, R.

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

Rarity, J. G.

A. Politi, M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-silicon waveguide quantum circuits,” Science 320(5876), 646–649 (2008).
[CrossRef] [PubMed]

J. G. Rarity and P. R. Tapster, “Experimental violation of Bell’s inequality based on phase and momentum,” Phys. Rev. Lett. 64(21), 2495–2498 (1990).
[CrossRef] [PubMed]

Reck, M.

G. Weihs, M. Reck, H. Weinfurter, and A. Zeilinger, “Two-photon interference in optical fiber multiports,” Phys. Rev. A 54(1), 893–897 (1996).
[CrossRef] [PubMed]

M. Reck, A. Zeilinger, H. J. Bernstein, and P. Bertani, “Experimental realization of any discrete unitary operator,” Phys. Rev. Lett. 73(1), 58–61 (1994).
[CrossRef] [PubMed]

Redhead, M. L. G.

P. Heywood and M. L. G. Redhead, “Nonlocality and the Kochen-Specker paradox,” Found. Phys. 13(5), 481–499 (1983).
[CrossRef]

Roberts, T. D.

Rossi, A.

A. Rossi, G. Vallone, A. Chiuri, F. De Martini, and P. Mataloni, “Multipath entanglement of two photons,” Phys. Rev. Lett. 102(15), 153902 (2009).
[CrossRef] [PubMed]

Saleh, B. E. A.

Saleh, M. F.

Sansoni, L.

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

Sciarrino, F.

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

Shadbolt, P. J.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Shapiro, J. H.

Sharping, J. E.

X. Li, P. L. Voss, J. E. Sharping, and P. Kumar, “Optical-fiber source of polarization-entangled photons in the 1550 nm telecom band,” Phys. Rev. Lett. 94(5), 053601 (2005).
[CrossRef] [PubMed]

Shimony, A.

M. A. Horne, A. Shimony, and A. Zeilinger, “Two-particle interferometry,” Phys. Rev. Lett. 62(19), 2209–2212 (1989).
[CrossRef] [PubMed]

J. F. Clauser, M. A. Horne, A. Shimony, and R. A. Holt, “Proposed experiment to test local hidden-variable theories,” Phys. Rev. Lett. 23(15), 880–884 (1969).
[CrossRef]

Silberberg, Y.

Y. Bromberg, Y. Lahini, R. Morandotti, and Y. Silberberg, “Quantum and classical correlations in waveguide lattices,” Phys. Rev. Lett. 102(25), 253904 (2009).
[CrossRef] [PubMed]

Smith, B. J.

Smith, P. G. R.

Spillane, S. M.

Steinberg, A. M.

M. Mohseni, A. M. Steinberg, and J. A. Bergou, “Optical realization of optimal unambiguous discrimination for pure and mixed quantum states,” Phys. Rev. Lett. 93(20), 200403 (2004).
[CrossRef] [PubMed]

Szameit, A.

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

Takesue, H.

Tanzilli, S.

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Tapster, P. R.

J. G. Rarity and P. R. Tapster, “Experimental violation of Bell’s inequality based on phase and momentum,” Phys. Rev. Lett. 64(21), 2495–2498 (1990).
[CrossRef] [PubMed]

Teich, M. C.

Thomas-Peter, N.

Thompson, M. G.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Tittel, H.

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Tünnermann, A.

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

Vallone, G.

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

A. Rossi, G. Vallone, A. Chiuri, F. De Martini, and P. Mataloni, “Multipath entanglement of two photons,” Phys. Rev. Lett. 102(15), 153902 (2009).
[CrossRef] [PubMed]

Verde, M. R.

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Voss, P. L.

X. Li, P. L. Voss, J. E. Sharping, and P. Kumar, “Optical-fiber source of polarization-entangled photons in the 1550 nm telecom band,” Phys. Rev. Lett. 94(5), 053601 (2005).
[CrossRef] [PubMed]

Walmsley, I. A.

Weihs, G.

G. Weihs, M. Reck, H. Weinfurter, and A. Zeilinger, “Two-photon interference in optical fiber multiports,” Phys. Rev. A 54(1), 893–897 (1996).
[CrossRef] [PubMed]

Weinfurter, H.

K. Mattle, H. Weinfurter, P. G. Kwiat, and A. Zeilinger, “Dense coding in experimental quantum communication,” Phys. Rev. Lett. 76(25), 4656–4659 (1996).
[CrossRef] [PubMed]

G. Weihs, M. Reck, H. Weinfurter, and A. Zeilinger, “Two-photon interference in optical fiber multiports,” Phys. Rev. A 54(1), 893–897 (1996).
[CrossRef] [PubMed]

White, A. G.

G. J. Pryde and A. G. White, “Creation of maximally entangled photon-number states using optical fiber multiports,” Phys. Rev. A 68(5), 052315 (2003).
[CrossRef]

D. F. V. James, P. G. Kwiat, W. J. Munro, and A. G. White, “Measurement of qubits,” Phys. Rev. A 64(5), 052312 (2001).
[CrossRef]

Wong, F. N.

Xie, X.

Yamamoto, Y.

Yu, S.

A. Politi, M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-silicon waveguide quantum circuits,” Science 320(5876), 646–649 (2008).
[CrossRef] [PubMed]

Zbinden, P.

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Zeilinger, A.

X. Ma, S. Zotter, J. Kofler, T. Jennewein, and A. Zeilinger, “Experimental generation of single photons via active multiplexing,” Phys. Rev. A 83(4), 043814 (2011).
[CrossRef]

M. Zukowski, A. Zeilinger, and M. A. Horne, “Realizable higher-dimensional two-particle entanglements via multiport beam splitters,” Phys. Rev. A 55(4), 2564–2579 (1997).
[CrossRef]

K. Mattle, H. Weinfurter, P. G. Kwiat, and A. Zeilinger, “Dense coding in experimental quantum communication,” Phys. Rev. Lett. 76(25), 4656–4659 (1996).
[CrossRef] [PubMed]

G. Weihs, M. Reck, H. Weinfurter, and A. Zeilinger, “Two-photon interference in optical fiber multiports,” Phys. Rev. A 54(1), 893–897 (1996).
[CrossRef] [PubMed]

M. Reck, A. Zeilinger, H. J. Bernstein, and P. Bertani, “Experimental realization of any discrete unitary operator,” Phys. Rev. Lett. 73(1), 58–61 (1994).
[CrossRef] [PubMed]

M. A. Horne, A. Shimony, and A. Zeilinger, “Two-particle interferometry,” Phys. Rev. Lett. 62(19), 2209–2212 (1989).
[CrossRef] [PubMed]

Zhang, Q.

Zotter, S.

X. Ma, S. Zotter, J. Kofler, T. Jennewein, and A. Zeilinger, “Experimental generation of single photons via active multiplexing,” Phys. Rev. A 83(4), 043814 (2011).
[CrossRef]

Zukowski, M.

M. Zukowski, A. Zeilinger, and M. A. Horne, “Realizable higher-dimensional two-particle entanglements via multiport beam splitters,” Phys. Rev. A 55(4), 2564–2579 (1997).
[CrossRef]

Zyczkowski, K.

T. Durt, B.-G. Englert, I. Bengtsson, and K. Życzkowski, “On mutually unbiased bases,” Int. J. Quantum Inf. 8(04), 535–640 (2010).
[CrossRef]

Electron. Lett. (1)

S. Tanzilli, H. De Riedmatten, H. Tittel, P. Zbinden, P. Baldi, M. De Micheli, D. B. Ostrowsky, and N. Gisin, “Highly efficient photon-pair source using periodically poled lithium niobate waveguide,” Electron. Lett. 37(1), 26–28 (2001).
[CrossRef]

Found. Phys. (1)

P. Heywood and M. L. G. Redhead, “Nonlocality and the Kochen-Specker paradox,” Found. Phys. 13(5), 481–499 (1983).
[CrossRef]

Int. J. Quantum Inf. (1)

T. Durt, B.-G. Englert, I. Bengtsson, and K. Życzkowski, “On mutually unbiased bases,” Int. J. Quantum Inf. 8(04), 535–640 (2010).
[CrossRef]

Nat. Photonics (1)

P. J. Shadbolt, M. R. Verde, A. Peruzzo, A. Politi, A. Laing, M. Lobino, J. C. F. Matthews, M. G. Thompson, and J. L. O’Brien, “Generating, manipulating and measuring entanglement and mixture with a reconfigurable photonic circuit,” Nat. Photonics 6(1), 45–49 (2011).
[CrossRef]

Opt. Express (4)

Opt. Lett. (1)

Phys. Rev. A (8)

X. Ma, S. Zotter, J. Kofler, T. Jennewein, and A. Zeilinger, “Experimental generation of single photons via active multiplexing,” Phys. Rev. A 83(4), 043814 (2011).
[CrossRef]

D. F. V. James, P. G. Kwiat, W. J. Munro, and A. G. White, “Measurement of qubits,” Phys. Rev. A 64(5), 052312 (2001).
[CrossRef]

Z. Liu and H. Fan, “Decay of multiqudit entanglement,” Phys. Rev. A 79(6), 064305 (2009).
[CrossRef]

R. Keil, A. Szameit, F. Dreisow, M. Heinrich, S. Nolte, and A. Tünnermann, “Photon correlations in two-dimensional waveguide arrays and their classical estimate,” Phys. Rev. A 81(2), 023834 (2010).
[CrossRef]

G. Weihs, M. Reck, H. Weinfurter, and A. Zeilinger, “Two-photon interference in optical fiber multiports,” Phys. Rev. A 54(1), 893–897 (1996).
[CrossRef] [PubMed]

M. Zukowski, A. Zeilinger, and M. A. Horne, “Realizable higher-dimensional two-particle entanglements via multiport beam splitters,” Phys. Rev. A 55(4), 2564–2579 (1997).
[CrossRef]

G. J. Pryde and A. G. White, “Creation of maximally entangled photon-number states using optical fiber multiports,” Phys. Rev. A 68(5), 052315 (2003).
[CrossRef]

Y. L. Lim and A. Beige, “Multiphoton entanglement through a Bell multiport beam splitter,” Phys. Rev. A 71(6), 062311 (2005).
[CrossRef]

Phys. Rev. Lett. (12)

M. Mohseni, A. M. Steinberg, and J. A. Bergou, “Optical realization of optimal unambiguous discrimination for pure and mixed quantum states,” Phys. Rev. Lett. 93(20), 200403 (2004).
[CrossRef] [PubMed]

N. J. Cerf, M. Bourennane, A. Karlsson, and N. Gisin, “Security of quantum key distribution using d-level systems,” Phys. Rev. Lett. 88(12), 127902 (2002).
[CrossRef] [PubMed]

K. Mattle, H. Weinfurter, P. G. Kwiat, and A. Zeilinger, “Dense coding in experimental quantum communication,” Phys. Rev. Lett. 76(25), 4656–4659 (1996).
[CrossRef] [PubMed]

M. Reck, A. Zeilinger, H. J. Bernstein, and P. Bertani, “Experimental realization of any discrete unitary operator,” Phys. Rev. Lett. 73(1), 58–61 (1994).
[CrossRef] [PubMed]

Y. Bromberg, Y. Lahini, R. Morandotti, and Y. Silberberg, “Quantum and classical correlations in waveguide lattices,” Phys. Rev. Lett. 102(25), 253904 (2009).
[CrossRef] [PubMed]

X. Li, P. L. Voss, J. E. Sharping, and P. Kumar, “Optical-fiber source of polarization-entangled photons in the 1550 nm telecom band,” Phys. Rev. Lett. 94(5), 053601 (2005).
[CrossRef] [PubMed]

A. Cabello, “Proposal for revealing quantum nonlocality via local contextuality,” Phys. Rev. Lett. 104(22), 220401 (2010).
[CrossRef] [PubMed]

J. F. Clauser, M. A. Horne, A. Shimony, and R. A. Holt, “Proposed experiment to test local hidden-variable theories,” Phys. Rev. Lett. 23(15), 880–884 (1969).
[CrossRef]

L. Sansoni, F. Sciarrino, G. Vallone, P. Mataloni, A. Crespi, R. Ramponi, and R. Osellame, “Polarization entangled state measurement on a chip,” Phys. Rev. Lett. 105(20), 200503 (2010).
[CrossRef] [PubMed]

M. A. Horne, A. Shimony, and A. Zeilinger, “Two-particle interferometry,” Phys. Rev. Lett. 62(19), 2209–2212 (1989).
[CrossRef] [PubMed]

J. G. Rarity and P. R. Tapster, “Experimental violation of Bell’s inequality based on phase and momentum,” Phys. Rev. Lett. 64(21), 2495–2498 (1990).
[CrossRef] [PubMed]

A. Rossi, G. Vallone, A. Chiuri, F. De Martini, and P. Mataloni, “Multipath entanglement of two photons,” Phys. Rev. Lett. 102(15), 153902 (2009).
[CrossRef] [PubMed]

Science (1)

A. Politi, M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-silicon waveguide quantum circuits,” Science 320(5876), 646–649 (2008).
[CrossRef] [PubMed]

Other (2)

M. Reck and A. Zeilinger, “Quantum phase tracing of correlated photons in optical multiports,” in Quantum Interferometry, F. DeMartini, and A. Zeilinger, eds. (World Scientific, 1994), pp. 170–177.

M. A. Horne and A. Zeilinger, “A Bell-type EPR experiment using linear momenta,” in Symposium on the Foundations of Modern Physics, P. Lahti and P. Mittelstaedt, eds. (World Scientific, 1985), pp. 435–439.

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Figures (3)

Fig. 1
Fig. 1

Example of a setup for creating and manipulating path-entangled quNit pairs. a.) N non-linear crystal waveguides (ppLN) are used offering the feature of integration together with a higher down-conversion efficiency compared to bulk crystals [18,32]. All N crystals are coherently pumped by a common pump beam λ split on a NxN beam splitter. With a certain probability a photon pair is created via type-I spontaneous parametric down-conversion (SPDC): λ λ A + λ B . Due to the small conversion probability, the possibility of multiple SPDC events occurring in one or more crystals at the same time is negligible. Therefore, coherent pumping of N crystals will result in a superposition of the SPDC event happening in one of the N ppLN crystals. In the following step the SPDC pairs ( λ A , λ B ) in each mode (1,2,…,N) are separated by their wavelength using N dense wavelength division multiplexers (DWDM) into the two modes 1( 1 A , 1 B ), .... , N( N A , N B ) . After regrouping the modes by their wavelength, a path-entangled two quNit state is obtained as given in Eq. (1). b.) Each photon then enters an NxN multiport, realized by a combination of phase shifters and beam splitters. By choosing the appropriate phase ( φ i ) and reflectivity ( R i ) settings any arbitrary N-dimensional unitary transformation can be realized [4]. Combined with single photon detection a projective measurement is finally realized (section 2.1).

Fig. 2
Fig. 2

The experimental setup for creating two path entangled qubits. a.) The pump beam λ is split by a variable beam splitter (BS) into the two modes 1 and 2. The splitting ratio is adjusted by changing the distance between the two fibers using a micrometer screw. Each mode enters a non-linear periodically poled Lithium Niobate waveguide (ppLN) creating photon pairs via spontaneous parametric down-conversion. Cascaded dense wavelength division multiplexers (DWDM) separate and spectrally filter the down-converted photon pairs. Modes 1 and 2 (1’ and 2’) define a path-encoded qubit. This leads to the two qubit path-entangled state. Delay lines ( τ ) and polarization controller (PC) are used to adjust the arrival time and polarization of each mode. b.) 50/50 Beam splitters (BSA, BSB) and phases ( φ A , φ B ). Combined with single photon detection the projective measurement | P (1/2 ,φ)><P(1/2 ,φ)| is realized (Eq. (2). Before entering the single photon detectors for coincidence detection (&) the signal and pump beams are separated using a WDM. For further separation an isolator (Iso) is added absorbing 775nm but passing 1550nm. After the WDM the separated pump beam is detected using standard photo diodes (PD). A PID controller uses this signal to stabilize the phase (sec. 3.3).

Fig. 3
Fig. 3

Real and imaginary parts of the density matrix element < i , j | ρ C |i,j> of the produced state ψ reconstructed by maximum likelihood estimation after systematic accidental noise subtraction [28]. Unlabeled data corresponds to measured values smaller than Re( ρ C )<0.005 and Im( ρ C )<0.0008 .

Equations (7)

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

|Ψ > = α 1 | 1 A , 1 B >+ α 2 e i φ 1 | 2 A , 2 B >+...+ α N e i φ N1 | N A , N B >,
| P (α,φ) A > = α | 1 A >+ 1α e i φ A | 2 A >,
V=(95.6±0.4)% , V C =(97.3±0.5)%
S CHSH =(2.70±0.03).
F=(96.86±0.15)% and T=(87.9±0.6)%.
F C =(99.44±0.06)% and T C =(97.9±0.2)%.
| Ψ N=4 > = α 1 | 1 A , 1 B >+ α 2 e i φ 1 | 2 A , 2 B >+ α 3 e i φ 2 | 3 A , 3 B >+ α 4 e i φ 3 | 4 A , 4 B >,

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