Multiphoton coherent population oscillation

TL;DR

This paper investigates how multiphoton interactions induce long-lived coherent population oscillations at subharmonic frequencies in a two-level system, revealing strong parametric interactions between electromagnetic field components.

Contribution

It demonstrates the emergence of CPO resonances at subharmonic frequencies due to multiphoton parametric interactions, expanding understanding of coherent phenomena in two-level systems.

Findings

CPO resonances appear at subharmonic frequencies under certain conditions

Strong parametric interactions occur between weak sideband components

Multiphoton processes significantly influence coherent population dynamics

Abstract

We study the bichromatic driving of a two-level system which displays long-lived coherent population oscillations (CPO). We show that under certain conditions, multiphoton parametric interaction leads to the appearance of CPO resonances at the subharmonic frequencies. In addition, in the region of the CPO resonances, there is strong parametric interaction between the weak sideband components of the electromagnetic field.