  We theoretically investigate the possibility of observing resonant activation
in the hopping dynamics of two-mode semiconductor lasers. We present a series
of simulations of a rate-equations model under random and periodic modulation
of the bias current. In both cases, for an optimal choice of the modulation
time-scale, the hopping times between the stable lasing modes attain a minimum.
The simulation data are understood by means of an effective one-dimensional
Langevin equation with multiplicative fluctuations. Our conclusions apply to
both Edge Emitting and Vertical Cavity Lasers, thus opening the way to several
experimental tests in such optical systems.
