TY - JOUR
T1 - Multiparticle state tomography
T2 - Hidden differences
AU - Adamson, R. B.A.
AU - Shalm, L. K.
AU - Mitchell, M. W.
AU - Steinberg, A. M.
PY - 2007
Y1 - 2007
N2 - We address the problem of completely characterizing multiparticle states including loss of information to unobserved degrees of freedom. In systems where nonclassical interference plays a role, such as linear-optics quantum gates, such information can degrade interference in two ways, by decoherence and by distinguishing the particles. Distinguishing information, often the limiting factor for quantum optical devices, is not correctly described by previous state-reconstruction techniques, which account only for decoherence. We extend these techniques and find that a single modified density matrix can completely describe partially coherent, partially distinguishable states. We use this observation to experimentally characterize two-photon polarization states in single-mode optical fiber.
AB - We address the problem of completely characterizing multiparticle states including loss of information to unobserved degrees of freedom. In systems where nonclassical interference plays a role, such as linear-optics quantum gates, such information can degrade interference in two ways, by decoherence and by distinguishing the particles. Distinguishing information, often the limiting factor for quantum optical devices, is not correctly described by previous state-reconstruction techniques, which account only for decoherence. We extend these techniques and find that a single modified density matrix can completely describe partially coherent, partially distinguishable states. We use this observation to experimentally characterize two-photon polarization states in single-mode optical fiber.
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U2 - 10.1103/PhysRevLett.98.043601
DO - 10.1103/PhysRevLett.98.043601
M3 - Article
AN - SCOPUS:33846494208
SN - 0031-9007
VL - 98
JO - Physical Review Letters
JF - Physical Review Letters
IS - 4
M1 - 043601
ER -