Molecular dynamics simulation of time-irreversibility of stationary heat flux

Molecular dynamics simulations are carried out to monitor heat flux directly, in both forward process and time-reversed process. Two weighted Nos-Hoover thermostats, whose temperatures are different independently, are attached to a Stillinger-Weber fcc crystal confined by reflective walls. With increasing temperature difference, phase-space collapse rate in the forward process decreased and the irreversibility of heat flux appeared earlier in time-reversed process. The irreversibility appeared earlier, with decreasing numbers of significant digits. Nevertheless, the values of phase-space collapse rate were almost same.