  In this work we study the stochastic resonance (SR) effect in a driven
dissipative Jaynes-Cummings model. The SR effect is systematically studied in
the semiclassical and full quantum frameworks and in both cases we find that
SRs simultaneously occur for the optical and atomic freedoms. In particular, at
zero temperature quantum SR can be induced merely by vacuum fluctuations. The
qualitative features of semiclassical SR and quantum SR are similar, but the
parameter region of quantum SR are shifted from the semiclassical region due to
the widely-used factorization in obtaining semiclassical equations of motion.
Our results provide a theoretical basis for experimentally observing and
studying the SR phenomenon of the Jaynes-Cummings model in the quantum regime.
