A simple system for neutron diffraction at 4 K and elevated pressures.

Abstract

We describe a unique cryogen-free closed-cycle refrigerator system using a beryllium-copper VX1 variant of the Paris-Edinburgh press, which enables approximately 3 GPa to be generated on a sample volume of 66 mm3, over the temperature range of 4 K-300 K. The main advantage of this system is its versatility; it has been designed to be fully compatible with the PEARL neutron powder-diffraction instrument at the ISIS facility, but is also compatible with several other instruments at the facility with minor modifications. We provide a full description of the system, along with representative data collected on PEARL from MnF2 at 13 K and 2.4 GPa.