Photon generation via the dynamical Casimir effect in an optomechanical cavity as a closed quantum system

NICOLÁS F. DEL GROSSO; FERNANDO C. LOMBARDO; PAULA I. VILLAR

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Lugar: New York; Año: 2019 vol. 100 p. 625161 - 6251611

1050-2947

We present an analytical and numerical analysis of the particle creation in an optomechanical cavity inparametric resonance. We treat both the electromagnetic field and the mirror as quantum degrees of freedom andstudy the dynamical evolution as a closed quantum system. We consider different initial states and investigate thespontaneous emission of photons from phonons in the mirror. We find that, for initial phononic number states,the evolution of the photon number can be described as a nonharmonic quantum oscillator, providing a usefultool so as to estimate the maximum and mean number of photons produced for arbitrary high energies. Theefficiency of this mechanism is further analyzed for a detuned cavity as well as the possibility of stimulating thephoton production by adding some initial ones to the cavity. We also find relationships for the maximum andmean entanglement between the mirror and the wall in these states. Additionally, we study coherent states forthe motion of the mirror to connect this model with previous results from quantum field theory with a classicalmirror. Finally, we study thermal states of phonons in the wall and the equilibration process that leads to astationary distribution.