Large Kerr nonlinearities on cavity-atom polaritons

TL;DR

This paper proposes a scheme to generate large Kerr nonlinearities in cavity-atom polaritons using quantum interference, enabling low-light optical switching and quantum information applications.

Contribution

It introduces a novel method to induce large Kerr nonlinearities in cavity QED systems via destructive interference with a control laser.

Findings

Achieves large Kerr nonlinearities on polaritons

Enables optical switching at ultra-low light levels

Potential applications in quantum information processing

Abstract

I analyze a scheme that is capable of producing large Kerr nonlinearities on cavity-atom polaritons in a cavity QED system consisting of multiple three-level atoms confined in a cavity mode. A weak control laser coupled to the atoms from free space induces destructive quantum interference in the polariton excitation of the coupled cavity-atom system and creates large Kerr nonlinearities on the intra-cavity light field. The scheme can be used for optical switching or cross-phase modulation of the cavity-atom polariton at ultra-low light levels, which may be useful for applications in quantum state manipulation in cavity QED, quantum measurements, and quantum logic gates.