A finite difference method for studying thermal deformation in a double-layered thin film with imperfect interfacial contact exposed to ultrashort pulsed lasers

Recently, we have developed a staggered finite difference method for studying thermal deformation in a two-dimensional double-layered metal film exposed to ultrashort pulsed lasers. The method was obtained based on the parabolic two-step heat transport equations. It accounts for the coupling effect between lattice temperature and strain rate, as well as for the hot-electron blast effect in momentum transfer. The developed methodology allows us to avoid non-physical oscillations in the solution as demonstrated by a series of numerical experiments. In this article, we extend our research to the case that the double-layered thin film is imperfect thermal contact at interface. Nonlinear interfacial condition for temperature is considered. The interfacial conditions for stress, strain, and displacement are derived.