Chinese Physics B

Wigner function of the thermo number states

Liyun Hu, Fan Hong‐Yi

Published Mar 1, 2009• 29 citations

Abstract

Based on thermo field dynamics (TFD) and using the thermo Wigner operator in the thermo entangled state representation we derive the Wigner function of number states at finite temperature (named thermo number states). The figure of Wigner function shows that its shape gets smoothed as the temperature rises, implying that the quantum noise becomes larger.

DOI: 10.1088/1674-1056/18/3/010

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