Acoustic tests of Lorentz symmetry using Bulk Acoustic Wave quartz oscillators

TL;DR

This paper introduces a novel method using quartz bulk acoustic wave oscillators to test Lorentz invariance in the neutron sector, achieving sensitivity limits and proposing improvements for fundamental physics experiments.

Contribution

It presents a new experimental approach employing acoustic resonators on a rotating table to detect Lorentz-invariance violations in the neutron sector.

Findings

Sensitivity to Lorentz violation limit of .2  2.2 imes 10^{-14} GeV

Method demonstrates potential for improved fundamental physics tests

First experimental bounds using acoustic oscillators for Lorentz symmetry

Abstract

A new method of probing Lorentz invariance in the neutron sector is described. The method is baed on stable quartz bulk acoustic wave oscillators compared on a rotating table. Due to Lorentz-invariance violation, the resonance frequencies of acoustic wave resonators depend on the direction in space via a corresponding dependence of masses of the constituent elements of solids. This dependence is measured via observation of oscillator phase noise built around such devices. The first such experiment now shows sensitivity to violation down to the limit $\tilde{c}^n_Q=(-1.8\pm2.2)\times 10^{-14}$ GeV. Methods to improve the sensitivity are described together with some other applications of the technology in tests of fundamental physics.