Single-photon spin-orbit entanglement violating a Bell-like inequality

Single photons emerging from Pancharatnam-Berry phase optical elements (q plates) exhibit entanglement in the degrees of freedom of spin and orbital angular momentum. We put forward an experimental scheme for probing the spin-orbit correlations of single photons. It is found that the Clauser-Horne-Shimony-Holt parameter S for the single-photon spin-orbit entangled state could be as high as 2√2, evidently violating the Bell-like inequality and thus invalidating the noncontextual hidden variable theories.

[1]  R. Loidl,et al.  Violation of a Bell-like inequality in single-neutron interferometry , 2003, Nature.

[2]  S. Pancharatnam,et al.  Generalized theory of interference and its applications , 1956 .

[3]  M Ritsch-Marte,et al.  Violation of a Bell inequality in two-dimensional orbital angular momentum state-spaces. , 2009, Optics express.

[4]  Christian Kurtsiefer,et al.  LETTER TO THE EDITOR: Secure communication with single-photon two-qubit states , 2001 .

[5]  L. Marrucci,et al.  Optical spin-to-orbital angular momentum conversion in inhomogeneous anisotropic media. , 2006, Physical review letters.

[6]  S. Pancharatnam,et al.  Generalized theory of interference, and its applications , 1956 .

[7]  F Sciarrino,et al.  Polarization control of single photon quantum orbital angular momentum states. , 2009, Optics express.

[8]  Howell,et al.  Quantum computation through entangling single photons in multipath interferometers , 2000, Physical review letters.

[9]  Somshubhro Bandyopadhyay,et al.  Bell's inequality for a single spin-1/2 particle and quantum contextuality , 2001 .

[10]  M. Padgett,et al.  Advances in optical angular momentum , 2008 .

[11]  Marco Fiorentino,et al.  Deterministic controlled-NOT gate for single-photon two-qubit quantum logic. , 2004, Physical review letters.

[12]  Lixiang Chen,et al.  Sorting photons of different rotational Doppler shifts (RDS) by orbital angular momentum of single-photon with spin-orbit-RDS entanglement. , 2008, Optics express.

[13]  Ebrahim Karimi,et al.  Optimal quantum cloning of orbital angular momentum photon qubits through Hong–Ou–Mandel coalescence , 2009, 1010.5214.

[14]  A. Shimony,et al.  Proposed Experiment to Test Local Hidden Variable Theories. , 1969 .

[15]  Weinfurter,et al.  Experiments towards falsification of noncontextual hidden variable theories , 2000, Physical review letters.

[16]  M. Berry.  The Adiabatic Phase and Pancharatnam's Phase for Polarized Light , 1987 .

[17]  A. Vaziri,et al.  Entanglement of the orbital angular momentum states of photons , 2001, Nature.

[18]  H. Weinfurter,et al.  Universal unitary gate for single-photon two-qubit states , 2001, quant-ph/0101064.

[19]  Ebrahim Karimi,et al.  Efficient generation and sorting of orbital angular momentum eigenmodes of light by thermally tuned q-plates , 2009, 0905.0562.

[20]  Kaige Wang,et al.  Quantum CNOT gates with orbital angular momentum and polarization of single-photon quantum logic , 2007 .

[21]  S. Barnett,et al.  Interferometric methods to measure orbital and spin, or the total angular momentum of a single photon. , 2004, Physical review letters.

[22]  Ebrahim Karimi,et al.  Light propagation in a birefringent plate with topological charge. , 2008, Optics letters.

[23]  David McGloin,et al.  Spin-to-orbital angular momentum conversion in a strongly focused optical beam. , 2007, Physical review letters.

[24]  Lixiang Chen,et al.  Electro-optically forbidden or enhanced spin-to-orbital angular momentum conversion in a focused light beam. , 2008, Optics letters.

[25]  Ebrahim Karimi,et al.  Quantum information transfer from spin to orbital angular momentum of photons. , 2008, Physical review letters.

[26]  S. J. van Enk,et al.  Single-particle entanglement , 2005 .

[27]  Enrique J. Galvez,et al.  Bell-inequality violations with single photons entangled in momentum and polarization , 2009 .

[28]  J. P. Woerdman,et al.  Orbital angular momentum of light and the transformation of Laguerre-Gaussian laser modes. , 1992, Physical review. A, Atomic, molecular, and optical physics.

[29]  Lixiang Chen,et al.  Increasing Shannon dimensionality by hyperentanglement of spin and fractional orbital angular momentum. , 2009, Optics letters.

[30]  Lorenzo Marrucci.  Rotating light with light: Generation of helical modes of light by spin-to-orbital angular momentum conversion in inhomogeneous liquid crystals , 2007, SPIE Optics + Optoelectronics.

[31]  Antonio Picón,et al.  Spin-induced angular momentum switching. , 2007, Optics letters.