Quantum Phonon Optics: Coherent and Squeezed Atomic Displacements

TL;DR

This paper explores the generation and manipulation of coherent and squeezed quantum phonon states, analyzing their quantum fluctuations and potential for noise reduction in atomic displacements using polariton techniques.

Contribution

It introduces methods to produce and analyze squeezed phonon states, including analytical calculations and a polariton-based approach for noise squeezing.

Findings

Squeezed phonon states can reduce quantum noise below zero-point levels.

Analytical expressions for atomic displacement fluctuations are derived.

Polariton methods enable effective phonon noise squeezing.

Abstract

In this paper we investigate coherent and squeezed quantum states of phonons. The latter allow the possibility of modulating the quantum fluctuations of atomic displacements below the zero-point quantum noise level of coherent states. The expectation values and quantum fluctuations of both the atomic displacement and the lattice amplitude operators are calculated in these states---in some cases analytically. We also study the possibility of squeezing quantum noise in the atomic displacement using a polariton-based approach.