B.I. Stepanov Institute of physics, Belarus

Recently, the experimental evidence for vibrational resonance (VR) in a multi-stable vertical-cavity surface-emitting laser (VCSEL) driven by two periodic signals with very different frequencies was reported [1I. It was also shown that the use of VR for studying multistability gives more complete picture about coexisting polarization states in a parameter space as compared to hysteretic behavior. In this report the experimental results of investigations of polarization multi-stability in a multimode VCSEL in a broad range of dc injection current and for different temperatures of the laser diode by the method of VR are presented. Depending on the experimental conditions a coexistence of three, four and five polarization states in the VCSEL was experimentally found. A numerical simulation performed in the framework of overdamped oscillator with a multi-well potential function which takes into consideration the asymmetry of both the shape and the position of the potential wells qualitatively explains some observed experimental features. 1. V.N. Chizhevsky, Experimental evidence of vibrational resonance in a multistable system, Phys. Rev. 89, 062914-5 (2014).