Phonon Squeezed States Generated by Second Order Raman Scattering

TL;DR

This paper explores the generation of phonon squeezed states via second order Raman scattering, analyzing quantum fluctuations and their impact on measurable properties like dielectric constant, supported by theoretical calculations and experimental comparisons.

Contribution

It introduces a detailed theoretical framework for generating and analyzing phonon squeezed states through second order Raman scattering, linking quantum fluctuations to observable effects.

Findings

Phonon squeezed states can be generated via second order Raman scattering.

Quantum fluctuations of atomic displacements can be reduced below zero-point noise.

Experimental results align with theoretical predictions.

Abstract

We study squeezed states of phonons, which allow a reduction in the quantum fluctuations of the atomic displacements to below the zero-point quantum noise level of coherent phonon states. We investigate the generation of squeezed phonon states using a second order Raman scattering process. We calculate the expectation values and fluctuations of both the atomic displacement and the lattice amplitude operators, as well as the effects of the phonon squeezed states on macroscopically measurable quantities, such as changes in the dielectric constant. These results are compared with recent experiments.