Abstract

We report an experimental demonstration of a bright highfidelity single-mode-optical-fiber source of polarization-entangled photon pairs. The source takes advantage of single-mode fiber optics, highly nonlinear microstructure fiber, judicious phase-matching, and the inherent stability provided by a Sagnac interferometer. With a modest average pump power (300 µW), we create all four Bell states with a detected two-photon coincidence rate of 7 kHz per bandwidth of 0.9 nm, in a spectral range of more than 20 nm. To characterize the purity of the states produced by this source, we use quantum-state tomography to reconstruct the corresponding density matrices, with fidelities of 95 % or more for each Bell state.

© 2007 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. E. Schrödinger, "Die gegenwärtige Situation in der Quantenmechanik," Naturwissenschaften 23, 807?812; 823?828; 844?849 (1935).
    [CrossRef]
  2. R. P. Feynman, R. B. Leighton, R. B. and M. L. Sands, The Feynman Lectures on Physics, (Addison-Wesley, Massachusetts, 1965) Vol. 3.
  3. C. H. Bennett and G. Brassard, in Proc. IEEE Intl. Conf. on Computers, Systems and Signal Processing 175?179 (IEEE, Bangalore, 1984).
  4. A. K. Ekert, "Quantum cryptography based on Bell's theorem," Phys. Rev. Lett. 67, 661-663 (1991).
    [CrossRef] [PubMed]
  5. C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
    [CrossRef] [PubMed]
  6. P. W. Shor, "Fault-tolerant quantum conputation," in Proc. 37th Symp. on Foundations of Computer Science 15-65 (IEEE Computer Society Press, Los Alamitos, 1996).
  7. N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145?195 (2002).
    [CrossRef]
  8. J. F. Clauser, in Quantum [Un]speakables: From Bell to Quantum Information, R. A. Bertlmann, and A. Zeilinger, eds., (Springer, Heidelberg, 2002) pg. 61? 98.
  9. M. A. Nielsen and I. L. Chaung, Quantum Computation and Quantum Information, (Cambridge University Press, 2000).
  10. D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
    [CrossRef]
  11. P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
    [CrossRef] [PubMed]
  12. N. Gisin and R. Thew, "Quantum Communication," Nat. Photonics 1, 165 ? 171 (2007).
    [CrossRef]
  13. D. C. Burnham and D. L. Weinberg, "Observation of simultaneity in parametric production of optical photon pairs," Phys. Rev. Lett. 25, 84-87 (1970).
    [CrossRef]
  14. P. G. Kwiat, E. Waks, A. G. White, I. Appelbaum, and P. H. Eberhard, "Ultrabright source of polarization-entangled photons," Phys. Rev. A 60, 773-776 (R) (1999).
    [CrossRef]
  15. C. Kurtsiefer, M. Oberparleiter and H. Weinfurter, "High-efficiency entangled photon pair collection in type-II parametric fluorescence," Phys. Rev. A 64, 023802 1-4 (2001).
    [CrossRef]
  16. J. Altepeter, E. Jeffrey, and P. G. Kwiat, "Phase-compensated ultra-bright source of entangled photons," Opt. Express 13, 8951-8959 (2005).
    [CrossRef] [PubMed]
  17. T. Kim, M. Fiorentino, and F. N. C. Wong, "Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer," Phys. Rev. A 73, 012316 (2006).
    [CrossRef]
  18. G. P. Agrawal, Nonlinear Fiber Optics, 2nd edition (Academic, New York, 1995).
  19. L. J. Wang, C. K. Hong, and S. R. Friberg, "Generation of correlated photons via four-wave mixing in optical fibres," J. Opt. B: Quantum Semiclassical Opt. 3, 346-352 (2001).
    [CrossRef]
  20. H. Takesue, and K. Inoue, "Generation of polarization-entangled photon pairs and violation of Bell's inequality using spontaneous four-wave mixing in a fiber loop," Phys. Rev. A, 70, 031802?031804 (R) (2004).
    [CrossRef]
  21. X. Li, P. L. Voss, JayE. Sharping, and P. Kumar, "Optical?fiber source of polarization-entangled photons in the 1550 nm Telecom Band," Phys. Rev. Lett. 94, 053601-053605 (2005).
    [CrossRef] [PubMed]
  22. A. Birks, J. C. Knight, and P. St. Russell, "Endlessly single-mode photonic crystal fiber," Opt. Lett. 22, 961-963 (1997).
    [CrossRef] [PubMed]
  23. J. Fan, A. Migdall, and L. J. Wang, "Efficient generation of correlated photon pairs in a microstructure fiber," Opt. Lett. 30, 3368-3370 (2005).
    [CrossRef]
  24. F. V. Daniel, P. G. Kwiat, W. J. Munro, and A. G. White, "On the measurement of qubits," Phys. Rev. A 64, 052312 1?23 (2001).
  25. J. Fan, and A. Migdall, "A broadband high spectral brightness fiber-based two-photon source," Opt. Express 15, 2915-2920 (2007).
    [CrossRef] [PubMed]
  26. J. Fan, M. D. Eisaman, and A. Migdall, "Bright phase-stable broadband fiber-based source of polarization-entangled photon pairs," Phys. Rev. A 76, 2043836 (2007).
    [CrossRef]

2007 (3)

N. Gisin and R. Thew, "Quantum Communication," Nat. Photonics 1, 165 ? 171 (2007).
[CrossRef]

J. Fan, M. D. Eisaman, and A. Migdall, "Bright phase-stable broadband fiber-based source of polarization-entangled photon pairs," Phys. Rev. A 76, 2043836 (2007).
[CrossRef]

J. Fan, and A. Migdall, "A broadband high spectral brightness fiber-based two-photon source," Opt. Express 15, 2915-2920 (2007).
[CrossRef] [PubMed]

2006 (1)

T. Kim, M. Fiorentino, and F. N. C. Wong, "Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer," Phys. Rev. A 73, 012316 (2006).
[CrossRef]

2005 (4)

X. Li, P. L. Voss, JayE. Sharping, and P. Kumar, "Optical?fiber source of polarization-entangled photons in the 1550 nm Telecom Band," Phys. Rev. Lett. 94, 053601-053605 (2005).
[CrossRef] [PubMed]

J. Altepeter, E. Jeffrey, and P. G. Kwiat, "Phase-compensated ultra-bright source of entangled photons," Opt. Express 13, 8951-8959 (2005).
[CrossRef] [PubMed]

J. Fan, A. Migdall, and L. J. Wang, "Efficient generation of correlated photon pairs in a microstructure fiber," Opt. Lett. 30, 3368-3370 (2005).
[CrossRef]

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

2002 (1)

N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145?195 (2002).
[CrossRef]

2001 (1)

L. J. Wang, C. K. Hong, and S. R. Friberg, "Generation of correlated photons via four-wave mixing in optical fibres," J. Opt. B: Quantum Semiclassical Opt. 3, 346-352 (2001).
[CrossRef]

1997 (2)

A. Birks, J. C. Knight, and P. St. Russell, "Endlessly single-mode photonic crystal fiber," Opt. Lett. 22, 961-963 (1997).
[CrossRef] [PubMed]

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

1993 (1)

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

1991 (1)

A. K. Ekert, "Quantum cryptography based on Bell's theorem," Phys. Rev. Lett. 67, 661-663 (1991).
[CrossRef] [PubMed]

1970 (1)

D. C. Burnham and D. L. Weinberg, "Observation of simultaneity in parametric production of optical photon pairs," Phys. Rev. Lett. 25, 84-87 (1970).
[CrossRef]

1935 (1)

E. Schrödinger, "Die gegenwärtige Situation in der Quantenmechanik," Naturwissenschaften 23, 807?812; 823?828; 844?849 (1935).
[CrossRef]

Altepeter, J.

Aspelmeyer, M.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

Bennett, C. H.

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

Birks, A.

Bouwmeester, D.

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

Brassard, G.

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

Burnham, D. C.

D. C. Burnham and D. L. Weinberg, "Observation of simultaneity in parametric production of optical photon pairs," Phys. Rev. Lett. 25, 84-87 (1970).
[CrossRef]

Crepeau, C.

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

Eibl, M.

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

Eisaman, M. D.

J. Fan, M. D. Eisaman, and A. Migdall, "Bright phase-stable broadband fiber-based source of polarization-entangled photon pairs," Phys. Rev. A 76, 2043836 (2007).
[CrossRef]

Ekert, A. K.

A. K. Ekert, "Quantum cryptography based on Bell's theorem," Phys. Rev. Lett. 67, 661-663 (1991).
[CrossRef] [PubMed]

Fan, J.

Fiorentino, M.

T. Kim, M. Fiorentino, and F. N. C. Wong, "Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer," Phys. Rev. A 73, 012316 (2006).
[CrossRef]

Friberg, S. R.

L. J. Wang, C. K. Hong, and S. R. Friberg, "Generation of correlated photons via four-wave mixing in optical fibres," J. Opt. B: Quantum Semiclassical Opt. 3, 346-352 (2001).
[CrossRef]

Gisin, N.

N. Gisin and R. Thew, "Quantum Communication," Nat. Photonics 1, 165 ? 171 (2007).
[CrossRef]

N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145?195 (2002).
[CrossRef]

Hong, C. K.

L. J. Wang, C. K. Hong, and S. R. Friberg, "Generation of correlated photons via four-wave mixing in optical fibres," J. Opt. B: Quantum Semiclassical Opt. 3, 346-352 (2001).
[CrossRef]

Jay, P. L.

X. Li, P. L. Voss, JayE. Sharping, and P. Kumar, "Optical?fiber source of polarization-entangled photons in the 1550 nm Telecom Band," Phys. Rev. Lett. 94, 053601-053605 (2005).
[CrossRef] [PubMed]

Jeffrey, E.

Jozsa, R.

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

Kim, T.

T. Kim, M. Fiorentino, and F. N. C. Wong, "Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer," Phys. Rev. A 73, 012316 (2006).
[CrossRef]

Knight, J. C.

Kwiat, P. G.

Li, X.

X. Li, P. L. Voss, JayE. Sharping, and P. Kumar, "Optical?fiber source of polarization-entangled photons in the 1550 nm Telecom Band," Phys. Rev. Lett. 94, 053601-053605 (2005).
[CrossRef] [PubMed]

Mattle, K.

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

Migdall, A.

Pan, J. W.

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

Peres, A.

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

Resch, K. J.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

Ribordy, G.

N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145?195 (2002).
[CrossRef]

Rudolph, T.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

Schenck, E.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

Schrödinger, E.

E. Schrödinger, "Die gegenwärtige Situation in der Quantenmechanik," Naturwissenschaften 23, 807?812; 823?828; 844?849 (1935).
[CrossRef]

St. Russell, P.

Thew, R.

N. Gisin and R. Thew, "Quantum Communication," Nat. Photonics 1, 165 ? 171 (2007).
[CrossRef]

Tittel, W.

N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145?195 (2002).
[CrossRef]

Vedral, V.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

Voss, P. L.

X. Li, P. L. Voss, JayE. Sharping, and P. Kumar, "Optical?fiber source of polarization-entangled photons in the 1550 nm Telecom Band," Phys. Rev. Lett. 94, 053601-053605 (2005).
[CrossRef] [PubMed]

Walther, P.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

Wang, L. J.

J. Fan, A. Migdall, and L. J. Wang, "Efficient generation of correlated photon pairs in a microstructure fiber," Opt. Lett. 30, 3368-3370 (2005).
[CrossRef]

L. J. Wang, C. K. Hong, and S. R. Friberg, "Generation of correlated photons via four-wave mixing in optical fibres," J. Opt. B: Quantum Semiclassical Opt. 3, 346-352 (2001).
[CrossRef]

Weinberg, D. L.

D. C. Burnham and D. L. Weinberg, "Observation of simultaneity in parametric production of optical photon pairs," Phys. Rev. Lett. 25, 84-87 (1970).
[CrossRef]

Weinfurter, H.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

Wong, F. N. C.

T. Kim, M. Fiorentino, and F. N. C. Wong, "Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer," Phys. Rev. A 73, 012316 (2006).
[CrossRef]

Wootters, W. K.

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

Zbinden, H.

N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145?195 (2002).
[CrossRef]

Zeilinger, A.

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

J. Opt. B: Quantum Semiclassical Opt. (1)

L. J. Wang, C. K. Hong, and S. R. Friberg, "Generation of correlated photons via four-wave mixing in optical fibres," J. Opt. B: Quantum Semiclassical Opt. 3, 346-352 (2001).
[CrossRef]

Nat. Photonics (1)

N. Gisin and R. Thew, "Quantum Communication," Nat. Photonics 1, 165 ? 171 (2007).
[CrossRef]

Nature (2)

D. Bouwmeester, J. W. Pan, K. Mattle, M. Eibl, H. Weinfurter, and A. Zeilinger, "Experimental quantum teleportation," Nature 390, 575 ?579 (1997).
[CrossRef]

P. Walther, K. J. Resch, T. Rudolph, E. Schenck, H. Weinfurter, V. Vedral, M. Aspelmeyer, A. Zeilinger, "Experimental one-way quantum computing," Nature 434, 169 ? 176 (2005).
[CrossRef] [PubMed]

Naturwissenschaften (1)

E. Schrödinger, "Die gegenwärtige Situation in der Quantenmechanik," Naturwissenschaften 23, 807?812; 823?828; 844?849 (1935).
[CrossRef]

Opt. Express (2)

Opt. Lett. (2)

Phys. Rev. A (2)

J. Fan, M. D. Eisaman, and A. Migdall, "Bright phase-stable broadband fiber-based source of polarization-entangled photon pairs," Phys. Rev. A 76, 2043836 (2007).
[CrossRef]

T. Kim, M. Fiorentino, and F. N. C. Wong, "Phase-stable source of polarization-entangled photons using a polarization Sagnac interferometer," Phys. Rev. A 73, 012316 (2006).
[CrossRef]

Phys. Rev. Lett. (4)

D. C. Burnham and D. L. Weinberg, "Observation of simultaneity in parametric production of optical photon pairs," Phys. Rev. Lett. 25, 84-87 (1970).
[CrossRef]

A. K. Ekert, "Quantum cryptography based on Bell's theorem," Phys. Rev. Lett. 67, 661-663 (1991).
[CrossRef] [PubMed]

C. H. Bennett, G. Brassard, C. Crepeau, R. Jozsa, A. Peres, and W. K. Wootters, "Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels," Phys. Rev. Lett.  70, 1895?1899 (1993).
[CrossRef] [PubMed]

X. Li, P. L. Voss, JayE. Sharping, and P. Kumar, "Optical?fiber source of polarization-entangled photons in the 1550 nm Telecom Band," Phys. Rev. Lett. 94, 053601-053605 (2005).
[CrossRef] [PubMed]

Rev. Mod. Phys. (1)

N. Gisin, G. Ribordy, W. Tittel, and H. Zbinden, "Quantum cryptography," Rev. Mod. Phys. 74, 145?195 (2002).
[CrossRef]

Other (10)

J. F. Clauser, in Quantum [Un]speakables: From Bell to Quantum Information, R. A. Bertlmann, and A. Zeilinger, eds., (Springer, Heidelberg, 2002) pg. 61? 98.

M. A. Nielsen and I. L. Chaung, Quantum Computation and Quantum Information, (Cambridge University Press, 2000).

P. W. Shor, "Fault-tolerant quantum conputation," in Proc. 37th Symp. on Foundations of Computer Science 15-65 (IEEE Computer Society Press, Los Alamitos, 1996).

R. P. Feynman, R. B. Leighton, R. B. and M. L. Sands, The Feynman Lectures on Physics, (Addison-Wesley, Massachusetts, 1965) Vol. 3.

C. H. Bennett and G. Brassard, in Proc. IEEE Intl. Conf. on Computers, Systems and Signal Processing 175?179 (IEEE, Bangalore, 1984).

P. G. Kwiat, E. Waks, A. G. White, I. Appelbaum, and P. H. Eberhard, "Ultrabright source of polarization-entangled photons," Phys. Rev. A 60, 773-776 (R) (1999).
[CrossRef]

C. Kurtsiefer, M. Oberparleiter and H. Weinfurter, "High-efficiency entangled photon pair collection in type-II parametric fluorescence," Phys. Rev. A 64, 023802 1-4 (2001).
[CrossRef]

G. P. Agrawal, Nonlinear Fiber Optics, 2nd edition (Academic, New York, 1995).

H. Takesue, and K. Inoue, "Generation of polarization-entangled photon pairs and violation of Bell's inequality using spontaneous four-wave mixing in a fiber loop," Phys. Rev. A, 70, 031802?031804 (R) (2004).
[CrossRef]

F. V. Daniel, P. G. Kwiat, W. J. Munro, and A. G. White, "On the measurement of qubits," Phys. Rev. A 64, 052312 1?23 (2001).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (3)

Fig. 1.
Fig. 1.

Experimental setup. After passing through a transmission grating, the 8 ps linearly polarized pump laser pulse (λP =740.7 nm, repetition rate=80 MHz) is sent to the Sagnac interferometer via the polarizing beam splitter (PBS). A 1.8 m long polarization-maintaining microstructure fiber is the nonlinear FWM medium with zero-dispersion wavelength λzdw =745±5 nm and nonlinearity γ=70 W-1km-1 at λ P. The H-end of fiber (with principal axis oriented horizontally) faces port B of PBS and the V-end of fiber (with principal axis oriented vertically) faces port A. Inset 1 shows the Raman gain spectral profile of our fibers as a function of detuning from the pump wavelength. Inset 2 shows the measured two-photon quantum-interference fringes for Bell state Φ-at four angle settings of θs for the polarization analyzer in the signal arm: θs =0°, 45°, 90°,-45° with λs =689.5 nm, λi =799.5 nm, Δλ=0.9 nm. The visibility, V=(C max-C min)/(C max+C min) is calculated with a sine-squaredfunction-fit, where C max and C min are the maximum and minimum coincidence count rates. λ/2: half-wave plate; λ/4: quarter-wave plate.

Fig. 2.
Fig. 2.

Density matrix reconstruction of all four Bell states. The ideal density matrix (which is real) and the reconstructed density matrix (real and imaginary parts) are shown for each of the four Bell states with λs =693 nm and λi =795 nm, along with the fidelities calculated from the reconstructed matrices.

Fig. 3.
Fig. 3.

Density matrix reconstruction of Bell state Ψ-produced at different wavelengths. The reconstructed density matrices are shown along with the fidelities calculated from the reconstructed matrices.

Metrics