Stability analysis of spin-polarized VCSELs

The ability to control the output polarization of spin-polarized VCSELs, by electrical injection and/or optical pumping of spin-polarized carriers, holds much potential for ultrafast all-optical elements. Research interest has been boosted by recent experimental demonstrations of electrically-pumped [1] and optically-pumped spin-VCSELs [2]. Such devices can exhibit rich dynamics due to the competition of spin-flip processes and birefringence. Stability maps for spin-VCSELs dynamics are reported here, for the first time to our knowledge, using the spin flip model (SFM) [3] and the largest Lyapunov exponent (LLE) method [4]. Our approach accounts for dichroism and birefringence with rates γa and γp, respectively, using the parameter set used in [5]. We choose fixed values of cavity decay rate κ= 125 ns1, carrier recombination rate γ = 1 ns1 and a γ = 0. The stability maps are presented in terms of polarization ellipticity P and normalized amplitude η of the pumping (electrical or optical); only negative values of P are shown since the results are symmetric about P = 0. © 2011 IEEE