R. Okamoto, J. L. O’Brien, H. F. Hofmann, and S. Takeuchi, “Realization of a Knill-Laflamme-Milburn C-NOT gate a photonic quantum circuit combining effective optical nonlinearities,” Proc. Natl. Acad. Sci. USA108, 10067–10071 (2011).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, H. F. Hofmann, and S. Takeuchi, “Analysis of experimental error sources in a linear-optics quantum gate,” New J. Phys.12, 043053 (2010).

[CrossRef]

T. Jennewein, R. Ursin, M. Aspelmeyer, and A. Zeilinger, “Performing high-quality multi-photon experiments with parametric down-conversion,” J. Phys. B42, 114008 (2009).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

R. Kaltenbaek, R. Prevedel, M. Aspelmeyer, and A. Zeilinger, “High-fidelity entanglement swapping with fully independent sources,” Phys. Rev. A79, 040302(R) (2009).

[CrossRef]

H. R. Zhang and R. P. Wang, “Theory of fourfold interference with photon pairs from spatially separated sources,” Phys. Rev. A75, 053804 (2007).

[CrossRef]

M. Barbieri, “Effects of frequency correlation in linear optical entangling gates operated with independent photons,” Phys. Rev. A76, 043825 (2007).

[CrossRef]

Y. Kawabe, H. Fujiwara, S. Takeuchi, and K. Sasaki, “Investigation of the spatial propagation properties of type-I parametric fluorescence by use of tuning curve filtering method,” Jpn. J. Appl. Phys.46, 5802–5808 (2007).

[CrossRef]

Y. Kawabe, H. Fujiwara, R. Okamoto, K. Sasaki, and S. Takeuchi, “Quantum interference fringes beating the diffraction limit,” Opt. Express15, 14244–14250 (2007).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, J. L. O’Brien, K. Sasaki, and S. Takeuchi, “Beating the standard quantum limit with four-entangled photons,” Science316, 726–729 (2007).

[CrossRef]
[PubMed]

R. Kaltenbaek, B. Blauensteiner, M. Zukowski, M. Aspelmeyer, and A. Zeilinger, “Experimental interference of independent photons,” Phys. Rev. Lett.96, 240502 (2006).

[CrossRef]
[PubMed]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, “Linear optics controlled-phase gate made simple,” Phys. Rev. Lett.95, 210505 (2005).

[CrossRef]
[PubMed]

R. Okamoto, H. F. Hofmann, S. Takeuchi, and K. Sasaki, “Demonstration of an optical quantum controlled-NOT gate without path interference,” Phys. Rev. Lett.95, 210506 (2005).

[CrossRef]
[PubMed]

V. Giovannetti, S. Lloyd, and L. Maccone, “Quantum-enhanced measurements: beating the standard quantum limit,” Science306, 1330–1336 (2004).

[CrossRef]
[PubMed]

S. M. Saltiel, K. Koynov, B. Agate, and W. Sibbett, “Second-harmonic generation with focused beams under conditions of large group-velocity mismatch,” J. Opt. Soc. Am. B21, 591–598 (2004).

[CrossRef]

J. L. O’Brien, G. J. Pryde, A. G. White, T. C. Ralph, and D. Branning, “Demonstration of an all-optical quantum controlled-NOT gate,” Nature (London)426, 264–267 (2003).

[CrossRef]

H. Lee, P. Kok, and J. P. Dowling, “A quantum Rosetta stone for interferometry,” J. Mod. Opt.49, 2325–2338 (2002).

[CrossRef]

T. C. Ralph, N. K. Langford, T. B. Bell, and A. G. White, “Linear optical controlled-NOT gate in the coincidence basis,” Phys. Rev. A65, 062324 (2002).

[CrossRef]

H. F. Hofmann and S. Takeuchi, “Quantum phase gate for photonic qubits using only beam splitters and postse-lection,” Phys. Rev. A66, 024308 (2002).

[CrossRef]

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

[CrossRef]

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

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

[CrossRef]

M. Zukowski, A. Zeilinger, and H. Weinfurter, “Entangling independent pulsed photon sources,” Ann. N.Y. Acad. Sci.755, 91–102 (1995).

[CrossRef]

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]

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

S. M. Saltiel, K. Koynov, B. Agate, and W. Sibbett, “Second-harmonic generation with focused beams under conditions of large group-velocity mismatch,” J. Opt. Soc. Am. B21, 591–598 (2004).

[CrossRef]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

T. Jennewein, R. Ursin, M. Aspelmeyer, and A. Zeilinger, “Performing high-quality multi-photon experiments with parametric down-conversion,” J. Phys. B42, 114008 (2009).

[CrossRef]

R. Kaltenbaek, R. Prevedel, M. Aspelmeyer, and A. Zeilinger, “High-fidelity entanglement swapping with fully independent sources,” Phys. Rev. A79, 040302(R) (2009).

[CrossRef]

R. Kaltenbaek, B. Blauensteiner, M. Zukowski, M. Aspelmeyer, and A. Zeilinger, “Experimental interference of independent photons,” Phys. Rev. Lett.96, 240502 (2006).

[CrossRef]
[PubMed]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

M. Barbieri, “Effects of frequency correlation in linear optical entangling gates operated with independent photons,” Phys. Rev. A76, 043825 (2007).

[CrossRef]

T. C. Ralph, N. K. Langford, T. B. Bell, and A. G. White, “Linear optical controlled-NOT gate in the coincidence basis,” Phys. Rev. A65, 062324 (2002).

[CrossRef]

C. H. Bennett and G. Brassard, “Quantum cryptography: public key distribution and coin tossing,” Proceedings of IEEE International Conference on Computers Systems and Signal Processing175–179 (1984).

R. Kaltenbaek, B. Blauensteiner, M. Zukowski, M. Aspelmeyer, and A. Zeilinger, “Experimental interference of independent photons,” Phys. Rev. Lett.96, 240502 (2006).

[CrossRef]
[PubMed]

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

J. L. O’Brien, G. J. Pryde, A. G. White, T. C. Ralph, and D. Branning, “Demonstration of an all-optical quantum controlled-NOT gate,” Nature (London)426, 264–267 (2003).

[CrossRef]

C. H. Bennett and G. Brassard, “Quantum cryptography: public key distribution and coin tossing,” Proceedings of IEEE International Conference on Computers Systems and Signal Processing175–179 (1984).

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

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

H. Lee, P. Kok, and J. P. Dowling, “A quantum Rosetta stone for interferometry,” J. Mod. Opt.49, 2325–2338 (2002).

[CrossRef]

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, R. Okamoto, K. Sasaki, and S. Takeuchi, “Quantum interference fringes beating the diffraction limit,” Opt. Express15, 14244–14250 (2007).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, S. Takeuchi, and K. Sasaki, “Investigation of the spatial propagation properties of type-I parametric fluorescence by use of tuning curve filtering method,” Jpn. J. Appl. Phys.46, 5802–5808 (2007).

[CrossRef]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

V. Giovannetti, S. Lloyd, and L. Maccone, “Quantum-enhanced measurements: beating the standard quantum limit,” Science306, 1330–1336 (2004).

[CrossRef]
[PubMed]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

R. Okamoto, J. L. O’Brien, H. F. Hofmann, and S. Takeuchi, “Realization of a Knill-Laflamme-Milburn C-NOT gate a photonic quantum circuit combining effective optical nonlinearities,” Proc. Natl. Acad. Sci. USA108, 10067–10071 (2011).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, H. F. Hofmann, and S. Takeuchi, “Analysis of experimental error sources in a linear-optics quantum gate,” New J. Phys.12, 043053 (2010).

[CrossRef]

R. Okamoto, H. F. Hofmann, S. Takeuchi, and K. Sasaki, “Demonstration of an optical quantum controlled-NOT gate without path interference,” Phys. Rev. Lett.95, 210506 (2005).

[CrossRef]
[PubMed]

H. F. Hofmann and S. Takeuchi, “Quantum phase gate for photonic qubits using only beam splitters and postse-lection,” Phys. Rev. A66, 024308 (2002).

[CrossRef]

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]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

T. Jennewein, R. Ursin, M. Aspelmeyer, and A. Zeilinger, “Performing high-quality multi-photon experiments with parametric down-conversion,” J. Phys. B42, 114008 (2009).

[CrossRef]

R. Kaltenbaek, R. Prevedel, M. Aspelmeyer, and A. Zeilinger, “High-fidelity entanglement swapping with fully independent sources,” Phys. Rev. A79, 040302(R) (2009).

[CrossRef]

R. Kaltenbaek, B. Blauensteiner, M. Zukowski, M. Aspelmeyer, and A. Zeilinger, “Experimental interference of independent photons,” Phys. Rev. Lett.96, 240502 (2006).

[CrossRef]
[PubMed]

R. Kaltenbaek, 2008 PhD Thesis.

Y. Kawabe, H. Fujiwara, R. Okamoto, K. Sasaki, and S. Takeuchi, “Quantum interference fringes beating the diffraction limit,” Opt. Express15, 14244–14250 (2007).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, S. Takeuchi, and K. Sasaki, “Investigation of the spatial propagation properties of type-I parametric fluorescence by use of tuning curve filtering method,” Jpn. J. Appl. Phys.46, 5802–5808 (2007).

[CrossRef]

N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, “Linear optics controlled-phase gate made simple,” Phys. Rev. Lett.95, 210505 (2005).

[CrossRef]
[PubMed]

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

[CrossRef]

H. Lee, P. Kok, and J. P. Dowling, “A quantum Rosetta stone for interferometry,” J. Mod. Opt.49, 2325–2338 (2002).

[CrossRef]

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

S. M. Saltiel, K. Koynov, B. Agate, and W. Sibbett, “Second-harmonic generation with focused beams under conditions of large group-velocity mismatch,” J. Opt. Soc. Am. B21, 591–598 (2004).

[CrossRef]

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

[CrossRef]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

T. C. Ralph, N. K. Langford, T. B. Bell, and A. G. White, “Linear optical controlled-NOT gate in the coincidence basis,” Phys. Rev. A65, 062324 (2002).

[CrossRef]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

H. Lee, P. Kok, and J. P. Dowling, “A quantum Rosetta stone for interferometry,” J. Mod. Opt.49, 2325–2338 (2002).

[CrossRef]

V. Giovannetti, S. Lloyd, and L. Maccone, “Quantum-enhanced measurements: beating the standard quantum limit,” Science306, 1330–1336 (2004).

[CrossRef]
[PubMed]

V. Giovannetti, S. Lloyd, and L. Maccone, “Quantum-enhanced measurements: beating the standard quantum limit,” Science306, 1330–1336 (2004).

[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]

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

[CrossRef]

T. Nagata, R. Okamoto, H. F. Hofmann, and S. Takeuchi, “Analysis of experimental error sources in a linear-optics quantum gate,” New J. Phys.12, 043053 (2010).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, J. L. O’Brien, K. Sasaki, and S. Takeuchi, “Beating the standard quantum limit with four-entangled photons,” Science316, 726–729 (2007).

[CrossRef]
[PubMed]

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

R. Okamoto, J. L. O’Brien, H. F. Hofmann, and S. Takeuchi, “Realization of a Knill-Laflamme-Milburn C-NOT gate a photonic quantum circuit combining effective optical nonlinearities,” Proc. Natl. Acad. Sci. USA108, 10067–10071 (2011).

[CrossRef]
[PubMed]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, J. L. O’Brien, K. Sasaki, and S. Takeuchi, “Beating the standard quantum limit with four-entangled photons,” Science316, 726–729 (2007).

[CrossRef]
[PubMed]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

J. L. O’Brien, G. J. Pryde, A. G. White, T. C. Ralph, and D. Branning, “Demonstration of an all-optical quantum controlled-NOT gate,” Nature (London)426, 264–267 (2003).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hofmann, and S. Takeuchi, “Realization of a Knill-Laflamme-Milburn C-NOT gate a photonic quantum circuit combining effective optical nonlinearities,” Proc. Natl. Acad. Sci. USA108, 10067–10071 (2011).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, H. F. Hofmann, and S. Takeuchi, “Analysis of experimental error sources in a linear-optics quantum gate,” New J. Phys.12, 043053 (2010).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, J. L. O’Brien, K. Sasaki, and S. Takeuchi, “Beating the standard quantum limit with four-entangled photons,” Science316, 726–729 (2007).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, R. Okamoto, K. Sasaki, and S. Takeuchi, “Quantum interference fringes beating the diffraction limit,” Opt. Express15, 14244–14250 (2007).

[CrossRef]
[PubMed]

R. Okamoto, H. F. Hofmann, S. Takeuchi, and K. Sasaki, “Demonstration of an optical quantum controlled-NOT gate without path interference,” Phys. Rev. Lett.95, 210506 (2005).

[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]

R. Kaltenbaek, R. Prevedel, M. Aspelmeyer, and A. Zeilinger, “High-fidelity entanglement swapping with fully independent sources,” Phys. Rev. A79, 040302(R) (2009).

[CrossRef]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

J. L. O’Brien, G. J. Pryde, A. G. White, T. C. Ralph, and D. Branning, “Demonstration of an all-optical quantum controlled-NOT gate,” Nature (London)426, 264–267 (2003).

[CrossRef]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

J. L. O’Brien, G. J. Pryde, A. G. White, T. C. Ralph, and D. Branning, “Demonstration of an all-optical quantum controlled-NOT gate,” Nature (London)426, 264–267 (2003).

[CrossRef]

T. C. Ralph, N. K. Langford, T. B. Bell, and A. G. White, “Linear optical controlled-NOT gate in the coincidence basis,” Phys. Rev. A65, 062324 (2002).

[CrossRef]

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

[CrossRef]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

S. M. Saltiel, K. Koynov, B. Agate, and W. Sibbett, “Second-harmonic generation with focused beams under conditions of large group-velocity mismatch,” J. Opt. Soc. Am. B21, 591–598 (2004).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, J. L. O’Brien, K. Sasaki, and S. Takeuchi, “Beating the standard quantum limit with four-entangled photons,” Science316, 726–729 (2007).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, R. Okamoto, K. Sasaki, and S. Takeuchi, “Quantum interference fringes beating the diffraction limit,” Opt. Express15, 14244–14250 (2007).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, S. Takeuchi, and K. Sasaki, “Investigation of the spatial propagation properties of type-I parametric fluorescence by use of tuning curve filtering method,” Jpn. J. Appl. Phys.46, 5802–5808 (2007).

[CrossRef]

R. Okamoto, H. F. Hofmann, S. Takeuchi, and K. Sasaki, “Demonstration of an optical quantum controlled-NOT gate without path interference,” Phys. Rev. Lett.95, 210506 (2005).

[CrossRef]
[PubMed]

N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, “Linear optics controlled-phase gate made simple,” Phys. Rev. Lett.95, 210505 (2005).

[CrossRef]
[PubMed]

S. M. Saltiel, K. Koynov, B. Agate, and W. Sibbett, “Second-harmonic generation with focused beams under conditions of large group-velocity mismatch,” J. Opt. Soc. Am. B21, 591–598 (2004).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hofmann, and S. Takeuchi, “Realization of a Knill-Laflamme-Milburn C-NOT gate a photonic quantum circuit combining effective optical nonlinearities,” Proc. Natl. Acad. Sci. USA108, 10067–10071 (2011).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, H. F. Hofmann, and S. Takeuchi, “Analysis of experimental error sources in a linear-optics quantum gate,” New J. Phys.12, 043053 (2010).

[CrossRef]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, J. L. O’Brien, K. Sasaki, and S. Takeuchi, “Beating the standard quantum limit with four-entangled photons,” Science316, 726–729 (2007).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, R. Okamoto, K. Sasaki, and S. Takeuchi, “Quantum interference fringes beating the diffraction limit,” Opt. Express15, 14244–14250 (2007).

[CrossRef]
[PubMed]

Y. Kawabe, H. Fujiwara, S. Takeuchi, and K. Sasaki, “Investigation of the spatial propagation properties of type-I parametric fluorescence by use of tuning curve filtering method,” Jpn. J. Appl. Phys.46, 5802–5808 (2007).

[CrossRef]

R. Okamoto, H. F. Hofmann, S. Takeuchi, and K. Sasaki, “Demonstration of an optical quantum controlled-NOT gate without path interference,” Phys. Rev. Lett.95, 210506 (2005).

[CrossRef]
[PubMed]

H. F. Hofmann and S. Takeuchi, “Quantum phase gate for photonic qubits using only beam splitters and postse-lection,” Phys. Rev. A66, 024308 (2002).

[CrossRef]

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

[CrossRef]

T. Jennewein, R. Ursin, M. Aspelmeyer, and A. Zeilinger, “Performing high-quality multi-photon experiments with parametric down-conversion,” J. Phys. B42, 114008 (2009).

[CrossRef]

N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, “Linear optics controlled-phase gate made simple,” Phys. Rev. Lett.95, 210505 (2005).

[CrossRef]
[PubMed]

H. R. Zhang and R. P. Wang, “Theory of fourfold interference with photon pairs from spatially separated sources,” Phys. Rev. A75, 053804 (2007).

[CrossRef]

N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, “Linear optics controlled-phase gate made simple,” Phys. Rev. Lett.95, 210505 (2005).

[CrossRef]
[PubMed]

N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, “Linear optics controlled-phase gate made simple,” Phys. Rev. Lett.95, 210505 (2005).

[CrossRef]
[PubMed]

M. Zukowski, A. Zeilinger, and H. Weinfurter, “Entangling independent pulsed photon sources,” Ann. N.Y. Acad. Sci.755, 91–102 (1995).

[CrossRef]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

J. L. O’Brien, G. J. Pryde, A. G. White, T. C. Ralph, and D. Branning, “Demonstration of an all-optical quantum controlled-NOT gate,” Nature (London)426, 264–267 (2003).

[CrossRef]

T. C. Ralph, N. K. Langford, T. B. Bell, and A. G. White, “Linear optical controlled-NOT gate in the coincidence basis,” Phys. Rev. A65, 062324 (2002).

[CrossRef]

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

T. Jennewein, R. Ursin, M. Aspelmeyer, and A. Zeilinger, “Performing high-quality multi-photon experiments with parametric down-conversion,” J. Phys. B42, 114008 (2009).

[CrossRef]

R. Kaltenbaek, R. Prevedel, M. Aspelmeyer, and A. Zeilinger, “High-fidelity entanglement swapping with fully independent sources,” Phys. Rev. A79, 040302(R) (2009).

[CrossRef]

R. Kaltenbaek, B. Blauensteiner, M. Zukowski, M. Aspelmeyer, and A. Zeilinger, “Experimental interference of independent photons,” Phys. Rev. Lett.96, 240502 (2006).

[CrossRef]
[PubMed]

M. Zukowski, A. Zeilinger, and H. Weinfurter, “Entangling independent pulsed photon sources,” Ann. N.Y. Acad. Sci.755, 91–102 (1995).

[CrossRef]

H. R. Zhang and R. P. Wang, “Theory of fourfold interference with photon pairs from spatially separated sources,” Phys. Rev. A75, 053804 (2007).

[CrossRef]

R. Kaltenbaek, B. Blauensteiner, M. Zukowski, M. Aspelmeyer, and A. Zeilinger, “Experimental interference of independent photons,” Phys. Rev. Lett.96, 240502 (2006).

[CrossRef]
[PubMed]

M. Zukowski, A. Zeilinger, and H. Weinfurter, “Entangling independent pulsed photon sources,” Ann. N.Y. Acad. Sci.755, 91–102 (1995).

[CrossRef]

M. Zukowski, A. Zeilinger, and H. Weinfurter, “Entangling independent pulsed photon sources,” Ann. N.Y. Acad. Sci.755, 91–102 (1995).

[CrossRef]

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

[CrossRef]

H. Lee, P. Kok, and J. P. Dowling, “A quantum Rosetta stone for interferometry,” J. Mod. Opt.49, 2325–2338 (2002).

[CrossRef]

S. M. Saltiel, K. Koynov, B. Agate, and W. Sibbett, “Second-harmonic generation with focused beams under conditions of large group-velocity mismatch,” J. Opt. Soc. Am. B21, 591–598 (2004).

[CrossRef]

T. Jennewein, R. Ursin, M. Aspelmeyer, and A. Zeilinger, “Performing high-quality multi-photon experiments with parametric down-conversion,” J. Phys. B42, 114008 (2009).

[CrossRef]

Y. Kawabe, H. Fujiwara, S. Takeuchi, and K. Sasaki, “Investigation of the spatial propagation properties of type-I parametric fluorescence by use of tuning curve filtering method,” Jpn. J. Appl. Phys.46, 5802–5808 (2007).

[CrossRef]

B. P. Lanyon, M. Barbieri, M. P. Almeida, T. Jennewein, T. C. Ralph, K. J. Resch, G. J. Pryde, J. L. O’Brien, A. Gilchrist, and A. G. White, “Simplifying quantum logic using higher-dimensional Hilbert spaces,” Nat. Phys.5, 134–140 (2009).

[CrossRef]

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

[CrossRef]

J. L. O’Brien, G. J. Pryde, A. G. White, T. C. Ralph, and D. Branning, “Demonstration of an all-optical quantum controlled-NOT gate,” Nature (London)426, 264–267 (2003).

[CrossRef]

T. Nagata, R. Okamoto, H. F. Hofmann, and S. Takeuchi, “Analysis of experimental error sources in a linear-optics quantum gate,” New J. Phys.12, 043053 (2010).

[CrossRef]

Y. Kawabe, H. Fujiwara, R. Okamoto, K. Sasaki, and S. Takeuchi, “Quantum interference fringes beating the diffraction limit,” Opt. Express15, 14244–14250 (2007).

[CrossRef]
[PubMed]

H. R. Zhang and R. P. Wang, “Theory of fourfold interference with photon pairs from spatially separated sources,” Phys. Rev. A75, 053804 (2007).

[CrossRef]

M. Barbieri, “Effects of frequency correlation in linear optical entangling gates operated with independent photons,” Phys. Rev. A76, 043825 (2007).

[CrossRef]

R. Kaltenbaek, R. Prevedel, M. Aspelmeyer, and A. Zeilinger, “High-fidelity entanglement swapping with fully independent sources,” Phys. Rev. A79, 040302(R) (2009).

[CrossRef]

T. C. Ralph, N. K. Langford, T. B. Bell, and A. G. White, “Linear optical controlled-NOT gate in the coincidence basis,” Phys. Rev. A65, 062324 (2002).

[CrossRef]

H. F. Hofmann and S. Takeuchi, “Quantum phase gate for photonic qubits using only beam splitters and postse-lection,” Phys. Rev. A66, 024308 (2002).

[CrossRef]

N. Boto, P. Kok, D. S. Abrams, S. L. Braunstein, C. P. Williams, and J. P. Dowling, “Quantum interferometric optical lithography: exploiting entanglement to beat the diffraction limit,” Phys. Rev. Lett.85, 2733–2736 (2000).

[CrossRef]
[PubMed]

N. K. Langford, T. J. Weinhold, R. Prevedel, K. J. Resch, A. Gilchrist, J. L. O’Brien, G. J. Pryde, and A. G. White, “Demonstration of a simple entangling optical gate and its use in Bell-state analysis,” Phys. Rev. Lett.95, 210504 (2005).

[CrossRef]
[PubMed]

N. Kiesel, C. Schmid, U. Weber, R. Ursin, and H. Weinfurter, “Linear optics controlled-phase gate made simple,” Phys. Rev. Lett.95, 210505 (2005).

[CrossRef]
[PubMed]

R. Okamoto, H. F. Hofmann, S. Takeuchi, and K. Sasaki, “Demonstration of an optical quantum controlled-NOT gate without path interference,” Phys. Rev. Lett.95, 210506 (2005).

[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]

R. Kaltenbaek, B. Blauensteiner, M. Zukowski, M. Aspelmeyer, and A. Zeilinger, “Experimental interference of independent photons,” Phys. Rev. Lett.96, 240502 (2006).

[CrossRef]
[PubMed]

R. Okamoto, J. L. O’Brien, H. F. Hofmann, and S. Takeuchi, “Realization of a Knill-Laflamme-Milburn C-NOT gate a photonic quantum circuit combining effective optical nonlinearities,” Proc. Natl. Acad. Sci. USA108, 10067–10071 (2011).

[CrossRef]
[PubMed]

V. Giovannetti, S. Lloyd, and L. Maccone, “Quantum-enhanced measurements: beating the standard quantum limit,” Science306, 1330–1336 (2004).

[CrossRef]
[PubMed]

T. Nagata, R. Okamoto, J. L. O’Brien, K. Sasaki, and S. Takeuchi, “Beating the standard quantum limit with four-entangled photons,” Science316, 726–729 (2007).

[CrossRef]
[PubMed]

R. Okamoto, J. L. O’Brien, H. F. Hoffman, T. Nagata, K. Sasaki, and S. Takeuchi, “An entanglement filter,” Science323, 483–485 (2009).

[CrossRef]
[PubMed]

C. H. Bennett and G. Brassard, “Quantum cryptography: public key distribution and coin tossing,” Proceedings of IEEE International Conference on Computers Systems and Signal Processing175–179 (1984).

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

R. Kaltenbaek, 2008 PhD Thesis.