Effect of Noise on Vibrational Resonance at the Beat Frequency in a Bistable Vertical-Cavity Surface-Emitting Laser with a Biharmonic Excitation

The results of an experimental and theoretical study of the effect of noise on the polarization dynamics of a bistable vertical-cavity surface-emitting laser (VCSEL) driven by two harmonic signals with the frequencies $f_{1}$ and $f_{2}= 2f_{1}+\delta$, where $\delta<f_{1}$ is the detuning frequency, is presented. In the noiseless case, the response amplitude at the beat frequency $\delta$ is higher than the response in conventional vibrational resonance (VR) at the frequency $f_{1}$. In the presence of noise, the method of the detection on the beat frequency can be more effective in a certain range of noise intensity as compared to the traditional VR method. The experimental results are in good agreement with the numerical results obtained within the framework of the model of a bistable overdamped oscillator.