  We present a modified Schwarzschild solution for a model of evaporation of a
black hole with information preservation. By drawing a direct analogy to the
quantum pure accelerating mirror (dynamical Casimir effect of a 1D horizon), we
derive a Schwarzschild metric with not only the usual Schwarzschild radius but
an additional length scale related to the Planck length. The black hole has
thermal particle production that leads to complete evaporation of the black
hole, resulting in non-divergent entanglement entropy, Page curve turn-over,
and an asymptotic quantum pure state with no information loss.
