# Clamp cell with $in$ $situ$ pressure monitoring for low-temperature neutron scattering measurements

## TL;DR

This paper introduces a clamp pressure cell designed for low-temperature neutron scattering experiments, enabling in-situ pressure monitoring up to 2 GPa through optical fluorescence techniques, facilitating precise pressure control during measurements.

## Contribution

A novel clamp pressure cell with optical access and in-situ pressure monitoring capability for neutron scattering at low temperatures and high pressures up to 2 GPa.

## Key findings

- Successfully fabricated and tested the pressure cell.
- Developed a new calibration curve for pressure-induced fluorescence shifts.
- Demonstrated real-time pressure monitoring during experiments.

## Abstract

A clamp pressure cell for neutron scattering experiments at low temperatures and in external magnetic fields under pressure up to 2~GPa has been fabricated and tested. The cell provides optical access to the sample space that allows instantaneous pressure determination during sample loading, cooling and measuring using ruby and/or samarium doped strontium tetraborate fluorescence monitoring. A new calibration curve of the pressure-induced shift of the $^7D_0 - ^5F_0$ (0-0) line in the fluorescent spectrum of SrB$_4$O$_7$:Sm$^{2+}$ for moderate pressures, $P\leqslant{2}$ GPa, is given.