Modern Physics Letters B

THERMOFIELD ANALYSIS OF MAGNON SQUEEZING STATE IN THE FERROMAGNET

QINFENG XU, Ze Cheng, Yunxia Ping

Published Aug 10, 2008• 0 citations

Abstract

In this paper, we introduce the self-consistent field approximation to treat with the nonlinear interaction among spin waves. Then temperature-dependent Bogoliubov transformation is introduced to generate a new representation which engenders the transition from the zero temperature to the finite temperature. At last, temperature-dependent quantum fluctuation properties of magnons are discussed in the thermal field. At lower temperature, we find that the fluctuation of spin-component at some given time regions can be below the zero-point fluctuation level of the vacuum state and exhibit a periodical squeezing behavior. In particular, these squeezed effects vanish with the increasing of temperature. These squeezing effects differ from the previous studies.

DOI: 10.1142/s0217984908016601

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