Wide Range Thin-FIlm Ceramic Metal-Alloy Thermometers with Low Magnetoresistance

TL;DR

This paper introduces a new ceramic-metal composite thermometer capable of accurate temperature measurements across a wide range, including very low temperatures, in high magnetic fields with minimal magnetoresistance.

Contribution

The development of a novel granular-metal oxide ceramic composite (cermet) thermometer formed by co-sputtering nichrome and silicon dioxide, suitable for high magnetic field and low temperature measurements.

Findings

Sensitive from room temperature to below 100 mK

Operates reliably in magnetic fields up to 35 Tesla

Exhibits low and easily correctable magnetoresistance

Abstract

Many thermal measurements in high magnetic fields require thermometers that are sensitive over a wide temperature range, are low mass, have a rapid thermal response, and have a minimal, easily correctable magnetoresistance. Here we report the development of a new granular-metal oxide ceramic composite (cermet) for this purpose formed by co-sputtering of the metallic alloy nichrome Ni$_{0.8}$Cr$_{0.2}$ and the insulator silcon dioxide SiO$_2$. The resulting thin films are sensitive enough to be used from room temperature down to below 100 mK in magnetic fields up to at least 35 tesla.