A search for disordered (glassy) phase in solid 3He deformed in situ

TL;DR

This study investigates the presence of a disordered (glassy) phase in solid 3He through pressure measurements, finding minimal evidence of such a phase and contrasting results with solid 4He where supersolid effects are observed.

Contribution

The paper provides the first precise pressure-based analysis of disordered phases in solid 3He, showing no significant glassy behavior unlike in solid 4He.

Findings

Main pressure contribution from phonons

No significant excess pressure indicating glassy phase

Differences from solid 4He in supersolid behavior

Abstract

A disordered (glassy) state has been searched in solid 3He deformed in the course of experiment employing precise measurements of pressure. The analysis of the temperature dependence of the crystal pressure measured at a constant volume shows that the main contribution to the pressure is made by the phonon subsystem, the influence of the disordered phase being very weak. Annealing of the deformed crystal does not affect this state. The results obtained differ greatly from the corresponding data for solid 4He measured in the region of supersolid effects where a pressure excessive in comparison to the phonon one was registered. The excess pressure had a quadratic dependence on temperature, which is typical of a disordered system. Absence of the excess pressure in solid 3He is unclear yet, some speculative interpretations are suggested.