Table-top NMR system for high-pressure studies with in-situ laser heating

TL;DR

This paper introduces a compact, table-top NMR system using permanent magnets capable of high-pressure and high-temperature measurements, enabling in-situ laser heating studies at extreme conditions without large superconducting magnets.

Contribution

The development of a portable, high-field NMR system suitable for high-pressure, high-temperature experiments with in-situ laser heating capabilities.

Findings

Successful recording of 1H-NMR spectra of Ice VII at 25 GPa.

Demonstration of high-pressure high-temperature NMR with H2O at 25 GPa and ~1063 K.

Use of signal intensity changes for temperature measurement in laser-heated NMR.

Abstract

High pressure Nuclear Magnetic Resonance (NMR) is known to uncover behavior of matter at extreme conditions. However, significant maintenance demands, space requirements and high costs of superconducting magnets render its application unfeasible for regular modern high pressure laboratories. Here, we present a table-top NMR system based on permanent Halbach magnet arrays with dimensions of 25 cm diameter and 4 cm height. At the highest field of 1013 mT, 1H-NMR spectra of Ice VII have been recorded at 25 GPa and ambient temperature. The table-top NMR system can be used together with double sided laser heating set-ups. Feasibility of high-pressure high-temperature NMR was demonstrated by collecting 1H-NMR spectra of H2O at 25 GPa and 1063(50) K. We found that the change in signal intensity in laser-heated NMR diamond anvil cell yields a convenient way for temperature measurements.