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

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 $Δ$ is determined. At $P=1.5$ GPa it is reduced to $Δ=0.79$ meV from $Δ=1.17$ 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.

5 pages, 4 figures