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arXiv · 1812.04348

Fringe visibility and distinguishability in two-path interferometer with an asymmetric beam splitter

Yanjun Liu·Jing Lu·Zhihui Peng·Lan Zhou·Dongning Zheng
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Abstract

We study the fringe visibility and the distinguishability of a general Mach-Zehnder interferometer with an asymmetric beam splitter. Both the fringe visibility V and the distinguishability D are affected by the input state of the particle characterized by the Bloch vector S=(Sx,Sy,Sz) and the second asymmetric beam splitter characterized by paramter /beta. For the total system is initially in a pure state, it is found that the fringe visibility reaches the upper bound and the distinguishability reaches the lower bound when cos(/beta) = -Sx. The fringe visibility obtain the maximum only if Sx = 0 and /beta = /pi/2 when the input particle is initially in a mixed state. The complementary relationship V2 + D2 <= 1 is proved in a general Mach-Zehnder interferometer with an asymmetric beam splitter, and the conditions for the equality are also presented.

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Yanjun Liu, Jing Lu, Zhihui Peng, Lan Zhou, Dongning Zheng. 2018-12-11. Fringe visibility and distinguishability in two-path interferometer with an asymmetric beam splitter. https://doi.org/10.1088/1674-1056/28/3/030303

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