Multiple nonequilibrium steady states for one-dimensional heat flow

A nonequilibrium molecular dynamics model of heat flow in one-dimensional lattices is shown to have multiple steady states for any fixed heat field strength ranging from zero to a certain positive value. We demonstrate that, depending on the initial conditions, there are at least two possibilities for the systems evolution: (i) formation of a stable traveling wave (soliton), and (ii) chaotic motion throughout the entire simulation. The percentage of the soliton-generating trajectories is zero for small field strength but increases sharply to unity over a critical region of the parameter.