An analog circuit experiment on vibrational resonance of an underdamped bistable system

The underdamped vibrational resonance of a bistable analogue circuit is investigated. For a wide range of damping coefficients, vibrational resonance phenomena are more robust than over‐damped states. In particular, the vibration resonance curve reenters from single peak to double peak and then to single peak again with the increase of damping coefficients, that is, a reentrance phenomenon. The experimental results are consistent with the theoretical ones. The experiment constructed a framework for amplifying weak signals within underdamped regimes.