Suppression of noise in a noisy optical trap

The concept of noise suppression in intrinsically noisy systems by adding noise at the input using a microscopic bead heald in a moving and intensity-modulated optical trap was explored and clarified. An experimental model system in which added fluctuations in the trap position result in reduced variance of the observed bead position as compared to a stationary trap was constructed by coupling the stiffness of the optical trap to its position. It was demonstrate that the essential aspects of noise reduction in such a system was that the added fluctuations drive the system into states with a reduced intensity of intrinsic noise sufficiently often. The trap positions were calculated to generate a fluctuating input state.