Optimal conditions for achieving strong third-order nonlinearity in semiconductor cavities

We determine the optimal conditions for achieving strong nonlinearity in semiconductor cavities as a function of the Q factor, coupling constant g, and longitudinal (gamma(1)) and pure transverse (gamma(2)) damping constants. The intensity of the third-order nonlinear field becomes maximum in the strong-coupling regime near the condition gamma(1) + 2 gamma(2) = omega(c)/2Q, where omega(c) is the cavity-quasi mode frequency. However, the most effective optical Kerr effect can be realized in the intermediate-coupling regime. Both of the nonlinearities are enhanced significantly also in the weak-coupling regime satisfying omega(c)/Q = (g(2)/gamma(1))[root 1+8 gamma(1)/(gamma(1)+2 gamma(2)) -1], and their intensities depend only on the damping constants.