[Stress-drop due to phonon scattering around dislocation core while it is in motion]

Unlike continuum, the motion of dislocation in nanoscale system induces unusual phenomenon. Through atomistic simulations, we observed that the internal effective stress of the system is always smaller than the externally applied stress during the dislocation motion. And we defined this unusual behavior as stress-drop for the first time. By using theoretical analysis, we proved that this behavior is induced by phonon scattering of elastic waves around anharmonic strain field of the core.