Ultra‐fast dynamic nonlinear mechanism of Fabry–Perot cavity with femtosecond pumping

Abstract

We numerically investigate the ultrafast dynamic nonlinear mechanism of an Fabry-Perot (FP) cavity with femtosecond (fs) pumping by the transmission change of an incident signal pulse. The nonlinear effect simulated by a twolevel system model can decrease the dielectric constant. Therefore, the temporally transmitted pulse is compressed owing to the faster phase velocity, and a sloped change in the transmission spectra is observed, which can be explained by the mechanism of pulse deformation. In addition, we stretched a certain part of the temporally transmitted pulse to further demonstrate the deformation of the pulse mechanism. This dynamic nonlinear mechanism based on the FP cavity can not only be used to design new optical devices with ultrafast response times, such as pulse modulators and passive amplifiers, but can also be easily constructed and integrated, which has great practical applications.