Evolution of time-delay signature of polarized chaos in a unidirectional-coupling VCSEL system with variable-polarization optical injection.

The evolution characteristics of the time-delay signature (TDS) of polarized chaos is systematically investigated in a unidirectional-coupling vertical-cavity surface-emitting (VCSEL) scheme with variable-polarization optical injection (VPOI), by means of the time series, optical spectra, power spectra, and autocorrelation function. In this scheme, the polarized chaos with TDS from a master VCSEL (M-VCSEL) with the external cavity is unidirectionally injected into another solitary slave VCSEL (S-VCSEL) through VPOI. The numerical results show that the VPOI can exert significant influence on the TDS characteristics of polarized chaos in the S-VCSEL. Under special injection parameters, as the polarization injection angle () of VPOI varies, the TDS evolution for the polarization component can exhibit almost an opposite evolutionary pattern to that for the polarization component in the S-VCSEL. A series of TDSs is mapped in the plane, and the injection strength and frequency detuning have been simulated to thoroughly elaborate the TDS evolution of polarization-resolved chaos in the S-VCSEL. Moreover, the optimal parameter spaces with effectively suppressed TDS are also determined for each polarization component in those maps.