Effect of pressure on the quantum spin ladder material IPA-CuCl3

TL;DR

This study investigates how hydrostatic pressure affects the spin gap in the quantum spin ladder material IPA-CuCl3, revealing a potential quantum phase transition at higher pressures through neutron scattering and magnetic susceptibility measurements.

Contribution

The paper provides the first detailed measurement of pressure dependence of the spin gap in IPA-CuCl3 and predicts a quantum phase transition at around 4 GPa.

Findings

Spin gap decreases from 1.17 meV to 0.79 meV at 1.5 GPa.

A predicted soft-mode quantum phase transition at approximately 4 GPa.

Structural phase transition complicates measurements.

Abstract

Inelastic neutron scattering and bulk magnetic susceptibility studies of the quantum S=1/2 spin ladder system IPA-CuCl3 are performed under hydrostatic pressure. The pressure dependence of the spin gap $\Delta$ is determined. At $P=1.5$ GPa it is reduced to $\Delta=0.79$ meV from $\Delta=1.17$ meV at ambient pressure. The results allow us to predict a soft-mode quantum phase transition in this system at P$_\mathrm{c}\sim 4$ GPa. The measurements are complicated by a proximity of a structural phase transition that leads to a deterioration of the sample.