A minimal mechanical device displaying bona fide stochastic resonance

A sphere in a shaken box with two connected compartments was monitored experimentally. The peaks of the residence time distribution appear at integer multiples of the driving period. The area below the first peak, the signal-to-noise ratio and the output signal power have maxima at a common value of the driving period Td. These maxima occur at the mimimum of TK/Td (TK: “Kramer's time”).