Measurements of a low temperature mechanical dissipation peak in a single layer of Ta2O5 doped with TiO2

TL;DR

This paper reports the first measurement of a low-temperature dissipation peak in TiO2-doped Ta2O5 coatings, revealing the source of mechanical loss that limits precision measurement systems and suggesting avenues for noise reduction.

Contribution

It provides the first experimental evidence of the dissipation mechanism in doped Ta2O5 coatings, crucial for reducing thermal noise in sensitive measurements.

Findings

Dissipation peak observed at 20 K in doped Ta2O5

First evidence of dissipation source in doped Ta2O5

Potential pathways for thermal noise reduction

Abstract

Thermal noise arising from mechanical dissipation in oxide coatings is a major limitation to many precision measurement systems, including optical frequency standards, high resolution optical spectroscopy and interferometric gravity wave detectors. Presented here are measurements of dissipation as a function of temperature between 7 K and 290 K in ion-beam sputtered Ta2O5 doped with TiO2, showing a loss peak at 20 K. Analysis of the peak provides the first evidence of the source of dissipation in doped Ta2O5 coatings, leading to possibilities for the reduction of thermal noise effects.