One-variable thermostats are studied as a generalization of the Nosé-Hoover method, which is aimed at achieving Gibbs' canonical distribution while conserving the time reversibility. A condition for equations of motion for the system with the thermostats is derived in the form of a partial differential equation. Solutions of this equation constitute a family of thermostats including the Nosé-Hoover method as the minimal solution. It is shown that the one-variable thermostat coupled with the one-dimensional harmonic oscillator loses its ergodicity with large enough relaxation time. The present result suggests that multivariable thermostats are required to assure the ergodicity and to work as a heat bath.
|ジャーナル||Physical Review E - Statistical, Nonlinear, and Soft Matter Physics|
|出版ステータス||Published - 2007 4月 3|
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