Stochastic resonance via single-ion phonon laser.

Stochastic resonance, a phenomenon that amplifies and detects weak signals, has been observed in various physical systems. However, due to the challenge of constructing controllable nonlinear damping, stochastic resonance has never been experimentally performed using van der Pol nonlinearity. Here, we report the experimental observation of stochastic resonance in a single trapped-ion phonon laser system exhibiting van der Pol nonlinearity. This experiment demonstrates the ability of the phonon laser to achieve stochastic resonance, amplifying weak signals via inputting additional noise at a single-atom level. Our experiment illustrates the single-ion phonon laser providing a platform to explore the physical properties of the nonlinear van der Pol oscillator. This work opens up a way for designing single-atomic devices for weak signal processing in real environments. [ABSTRACT FROM AUTHOR]