Threshold Displacement Energies of Oxygen in YBa$_2$Cu$_3$O$_7$: A Multi-Physics Analysis

TL;DR

This study uses multi-physics simulations to determine the threshold displacement energies of oxygen in YBa2Cu3O7, aiding understanding of radiation damage in high-temperature superconductors for fusion reactor applications.

Contribution

It introduces a combined molecular dynamics and DFT approach to accurately calculate oxygen TDEs in YBa2Cu3O7 at relevant temperatures.

Findings

Validated TDE values for all four oxygen sites.

Temperature-dependent analysis of TDEs at 25 K and 360 K.

Enhanced data for radiation damage modeling in HTS materials.

Abstract

Neutron bombardment of high temperature superconducting (HTS) magnets may compromise the integrity of the magnetic confinement in future fusion reactors. The amount of damage produced by a single neutron can be predicted from the threshold displacement energies (TDE) of the constituent ions in the HTS materials, such as the Rare Earth Cuperates. Therefore, in this work a Multiphysics simulation approach is adopted to determine the threshold displacement energies for oxygen in YBa2Cu3O7. Classical molecular dynamics (MD) simulations are employed to determine statistically representative TDEs for all four oxygen sites and these results are validated using Born-Oppenheimer MD employing forces derived from Density Functional Theory (DFT). The simulations were performed at the operational temperature (25 K) and the temperature of existing neutron irradiation studies (360 K) enabling a discussion about the relevance of this data. Overall, these findings enhance our understanding of radiation-induced damage in HTS materials and provide data that can be incorporated into higher order models offering critical insights into shielding design and magnet longevity.