The effect of externally applied pressure on the magnetic behavior of Cu2Te2O5(BrxCl{1-x})2

TL;DR

This study examines how external pressure influences the magnetic properties of Cu2Te2O5(BrxCl{1-x})2, revealing composition-dependent effects on transition temperatures and magnetic excitations through various neutron-based measurements.

Contribution

It provides new insights into the pressure dependence of magnetic behavior in Cu2Te2O5(BrxCl{1-x})2, highlighting contrasting effects in bromide and chloride compositions.

Findings

Transition temperatures increase with pressure for x=0 and 0.73.

Transition temperature decreases under pressure for x=1 (bromide).

Magnetic excitation peaks shift with pressure, indicating increased magnetic coupling.

Abstract

The effect of externally applied pressure on the magnetic behavior of Cu2Te2O5(BrxCl{1-x})2 with x = 0, 0.73 and 1, is investigated by a combination of magnetic susceptibility, neutron diffraction and neutron inelastic scattering measurements. The magnetic transition temperatures of the x = 0 and 0.73 compositions are observed to increase linearly with increasing pressure at a rate of 0.23(2) K/kbar and 0.04(1) K/kbar respectively. However, the bromide shows contrasting behavior with a large suppression of the transition temperature under pressure, at a rate of -0.95(9) K/kbar. In neutron inelastic scattering measurements of Cu2Te2O5Br2 under pressure only a small change to the ambient pressure magnetic excitations were observed. A peak in the density of states was seen to shift from ~5 meV in ambient pressure to ~6 meV under an applied pressure of 11.3 kbar, which was associated with an increase in the overall magnetic coupling strength.