2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/101540Can entanglement and the quantum behavior in physical systems survive at arbitrary high temperatures? In this Letter we show that this is the case for a electromagnetic field mode in an optical cavity with a movable mirror in a thermal state. We also identify two different dynamical regimes of generation of entanglement separated by a critical coupling strength.Accepted in Phys. Rev. LettQuantum Physicstext