Hysteresis cycles as a function of the detuning frequency between the CW laser and the M-VCSEL, Δω. Here, μ_M = μ_S = 1.2; K_Mx = K_My = 10 ns⁻¹; K_Sx = K_Sy = 50 ns⁻¹; E_inj = 0.6, T = 10 ns. The red solid line indicates the intensity of the x-polarization, the blue dashed line is that of the y-polarization. Panels (a) and (b) show the hysteresis cycles from the PPLN crystal output when E₀ = 0 kV/mm and E₀ = 85 kV/mm, respectively. Panels (c) and (d) show the hysteresis cycles from the S-VCSEL output when E₀ = 0 kV/mm and E₀ = 85 kV/mm, respectively. The arrows indicate the three levels used to encode the logic inputs (see text for details).