JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS, cilt.53, sa.18, 2020 (SCI-Expanded)
This paper computationally investigates the effect of the polarization decay rate (gamma), and the peak resonance frequency (f(0)) on optical parametric amplification inside a low-loss micro resonator. It is found that, for lower values of the polarization decay rate and the peak resonance frequency, the magnitude of amplification can be significantly higher. However, it was also observed that beyond a certain threshold value of the polarization decay rate, the gain factor of the amplification sharply reduces to a negligible value. This suggests that the polarization decay rate of a material has a more profound effect on wave attenuation for the case of nonlinear wave propagation as compared to the case of linear wave propagation. This gain enhancing effect of the low polarization decay rate requires the resonator walls to be highly reflective. We found that below a certain value of the mean reflection coefficient of the resonator walls, the amplification becomes insignificant regardless of the value of the polarization decay rate. Numerical simulations are performed using the finite difference time domain method and the resulting gain variations are plotted and tabulated with respect to the polarization decay rate, peak resonance frequency, and the mean reflection coefficient of the micro resonator to illustrate this drastic gain enhancement.