Asymmetric manipulations on the coherent Raman sideband generation under molecular modulations

Abstract

We study the light evolution through a Raman-active medium, where a pair of fields pump molecules near-resonantly and excite the molecular coherence. A synthetic lattice including multiple frequency sidebands via the coherent Raman process is constructed. By varying the density of molecules in the light propagation direction, the system can present a lattice model undergoing dynamic modulations. Further considering the frequency-dependent couplings between synthetic lattice sites, we explore intriguing phenomena, including spectral Bloch oscillation and super Bloch oscillation with asymmetric patterns, which leads to interesting frequency-conversion phenomena with the Raman sideband generations. Our work could be useful for future experiments in coherent Raman sideband processes towards ultrashort pulse generations and higher-frequency conversion.