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Title: Direct measurement of the density matrix of a two-photon polarization qubit
There is interest in using photon entanglement in biomedical applications. In one application, polarization-entangled photons pass through brain tissue. The effect of the brain tissue on the photon entanglement is measured via the decoherence that is imparted on the entangled state. Our current method to obtain a measure of the decoherence involves quantum state tomography, where a minimum of 16 measurements are used in conjunction with tomographic optimization to obtain the density matrix representing the state of the photons. In this work we report on a method to avoid tomographic optimization on behalf of a direct measurement of the elements of the density matrix. We make preliminary comparisons between the two methods.  more » « less
Award ID(s):
2011937
PAR ID:
10428778
Author(s) / Creator(s):
; ; ; ; ;
Editor(s):
Andrews, D.; Galvez, EJ; Rubinsztein-Dunlop, H.
Date Published:
Journal Name:
Proceedings of SPIE
Volume:
12373
Page Range / eLocation ID:
123730C
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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