TY - JOUR
T1 - Elementary test for nonclassicality based on measurements of position and momentum
AU - Fresta, Luca
AU - Borregaard, Johannes
AU - Sørensen, Anders Søndberg
PY - 2015/12/8
Y1 - 2015/12/8
N2 - We generalize a nonclassicality test described by Kot et al. [Phys. Rev. Lett. 108, 233601 (2012)PRLTAO0031-900710.1103/PhysRevLett.108.233601], which can be used to rule out any classical description of a physical system. The test is based on measurements of quadrature operators and works by proving a contradiction with the classical description in terms of a probability distribution in phase space. As opposed to the previous work, we generalize the test to include states without rotational symmetry in phase space. Furthermore, we compare the performance of the nonclassicality test with classical tomography methods based on the inverse Radon transform, which can also be used to establish the quantum nature of a physical system. In particular, we consider a nonclassicality test based on the so-called filtered back-projection formula. We show that the general nonclassicality test is conceptually simpler, requires less assumptions on the system, and is statistically more reliable than the tests based on the filtered back-projection formula. As a specific example, we derive the optimal test for quadrature squeezed single-photon states and show that the efficiency of the test does not change with the degree of squeezing.
AB - We generalize a nonclassicality test described by Kot et al. [Phys. Rev. Lett. 108, 233601 (2012)PRLTAO0031-900710.1103/PhysRevLett.108.233601], which can be used to rule out any classical description of a physical system. The test is based on measurements of quadrature operators and works by proving a contradiction with the classical description in terms of a probability distribution in phase space. As opposed to the previous work, we generalize the test to include states without rotational symmetry in phase space. Furthermore, we compare the performance of the nonclassicality test with classical tomography methods based on the inverse Radon transform, which can also be used to establish the quantum nature of a physical system. In particular, we consider a nonclassicality test based on the so-called filtered back-projection formula. We show that the general nonclassicality test is conceptually simpler, requires less assumptions on the system, and is statistically more reliable than the tests based on the filtered back-projection formula. As a specific example, we derive the optimal test for quadrature squeezed single-photon states and show that the efficiency of the test does not change with the degree of squeezing.
U2 - 10.1103/PhysRevA.92.062111
DO - 10.1103/PhysRevA.92.062111
M3 - Journal article
SN - 2469-9926
VL - 92
JO - Physical Review A
JF - Physical Review A
IS - 6
M1 - 062111
ER -