Uniaxial pressure dependencies of the phase boundary of TlCuCl_3

TL;DR

This study investigates how uniaxial pressure affects the phase boundary of TlCuCl_3, revealing highly anisotropic and substantial pressure dependencies of the magnetic transition, with implications for understanding quantum phase transitions.

Contribution

The paper provides the first detailed analysis of uniaxial pressure effects on TlCuCl_3's phase boundary using thermal expansion and magnetostriction measurements.

Findings

Uniaxial pressure causes large, anisotropic shifts in the phase boundary.

Transition field varies by approximately ±185 GPa depending on pressure direction.

Significant pressure dependencies suggest tunability of quantum phases.

Abstract

We present a thermal expansion and magnetostriction study of TlCuCl_3, which shows a magnetic-field induced transition from a spin gap phase to a Neel ordered phase. Using Ehrenfest relations we derive huge and strongly anisotropic uniaxial pressure dependencies of the respective phase boundary, e.g. the transition field changes by about $\pm 185$ GPa depending on the direction of uniaxial pressure.