Polarization-Resolved Nonlinear Dynamics Induced by Orthogonal Optical Injection in Long-Wavelength VCSELs

Abstract

We report a first experimental study of the polarization-resolved nonlinear dynamics of a 1550 nm singlemode VCSEL subject to orthogonal optical injection. Stability maps identifying the boundaries between regions of different nonlinear dynamics are reported for two different values of the bias current. A rich variety of nonlinear behaviours including periodic, period doubling, and irregular dynamics are observed for both polarizations. Polarization switching and injection locking induced by the optical injection are also included in the mapping. Analysis is given also in terms of the frequency detuning between the injected light and the orthogonal linear polarization of the VCSEL. When the frequency detuning is positive polarization switching can be observed in a periodic dynamical regime, including both period one and period two behaviors. For positive frequency detuning, the only polarization that contributes to the dynamics of the total power is the orthogonal polarization. For negative frequency detunings both linear polarizations contribute to the dynamics of the total power.

Correlation properties and time-resolved dynamics of linear polarizations emitted by single-mode vertical-cavity surface-emitting lasers subject to orthogonal optical injection

“…These include single-longitudinal mode operation, circular beam profile, reduced fabrication costs, ease of fabrication of two-dimensional arrays, etc. Studies of nonlinear dynamics of optically injected semiconductor lasers have been extended to VCSELs [6][7][8][9][10][11][12][13][14][15] since these devices offer additional degrees of freedom, like the presence of multiple transverse modes and the direction of the emitted polarization, when compared with their edge-emitting counterparts. The behavior of these systems not only includes the previously mentioned dynamical regimes but also polarization switching (PS) and optical bistability [16][17][18][19][20].…”

“…The specific injection scheme with orthogonally polarized master and slave lasers produces new features, like PS, that cannot be found when dealing with parallel optical injection. Nonlinear dynamics of VCSELs under orthogonal optical injection has been experimentally and theoretically analyzed for 850 [7][8][9][10][11][12] and 1550 nm [13][14][15] wavelength devices. Rich nonlinear dynamics, including period doubling, quasiperiodicity, injection locking, bistability, and chaos, have been found in short-wavelength VCSELs [7][8][9][10][11][12].…”

“…These devices were characterized by small values of birefringence and showed PS in absence of optical injection. Analysis of 1550 nm wavelength single transverse mode VCSELs subject to orthogonal optical injection have also shown limit cycle and period doubling dynamics, injection locking, irregular behavior [13][14][15], and bistability [18][19][20]. These long-wavelength devices were characterized by very large values of the birefringence parameter and by emission in a single linear polarization over the whole bias current range in absence of optical injection.…”

Investigation of vertical cavity surface emitting laser dynamics for neuromorphic photonic systems

“…3 and 4 can be explained from the effects induced by polarised optical injection. 19,21,22 Fig. 3 shows the case where PS appears associated with injection locking 19 (this is a situation in which the orthogonal polarization mode of the VCSEL locks to the injected field and has constant output intensity with emission at the wavelength of the external signal 15 ).…”

“…4(b), the parallel polarization is significantly attenuated but not completely suppressed. 19,21,22 In such cases, it has been demonstrated that the two polarized outputs of the VCSEL can both exhibit limit cycle dynamics. 21,22 This is the case here where an attenuated periodic signal is also obtained in the parallel polarization, showing a similar behaviour to the sub-threshold oscillations of biological neurons.…”