Noise induced stability in fluctuating, bistable potentials

The overdamped motion of a Brownian particle in an asymmetric, bistable, fl uctuating potential shows noise induced stability. For intermediate fluctua tion rates the mean occupancy of minima with an energy above the absolute m inimum is enhanced. The model works as a detector for potential fluctuation s being not too fast and not too slow. This effect occurs due to the differ ent time scales in the problem. We present a detailed analysis of this effe ct using the exact solution of the Fokker-Planck equation for a simple mode l. Further we show that for nut too fast fluctuations the system can be wel l described by effective rate equations. The results of the rate equations agree quantitatively with the exact results.