In this paper, we propose a heat jet approach for atomic simulations at finitetemperature. Thermal fluctuations are injected into an atomic subsystem from itsboundaries, without modifying the governing equations for the interior domain.More precisely, we design a two way local boundary condition, and take theincoming part of a phonon representation for thermal fluctuation input. In thisway, nonthermal wave propagation simulations are effectively performed at finitetemperature. We further apply this approach to nonlinear chains with the Morsepotential. Chains with model parameters fitted to carbon and gold are simulatedat room temperature with fidelity.
