Suppression of the Shastry-Sutherland phase in Ce$_{2}$Pd$_{2}$Sn at a field induced critical point

TL;DR

This study maps the magnetic phase diagram of Ce$_2$Pd$_2$Sn, showing the suppression of the Shastry-Sutherland phase at a critical magnetic field and revealing potential new phases near this critical point.

Contribution

It provides the first detailed analysis of the field-induced suppression of the Shastry-Sutherland phase in Ce$_2$Pd$_2$Sn and identifies a possible new phase formation at the critical point.

Findings

The upper magnetic transition is unaffected by fields up to 1 T.

The lower transition increases with field and merges with the upper transition at a critical point.

The Shastry-Sutherland phase is suppressed at the critical field of approximately 0.12 T.

Abstract

The magnetic phase diagram of Ce$_2$Pd$_2$Sn is investigated through the field dependence of thermal, transport and magnetic measurements performed at low temperature. The upper transition, $T_M=4.8$ K is practically not affected by magnetic field up to B=1 T, whereas the lower one $T_C(B)$ rapidly increases from 2.1 K joining $T_M$ in a critical point at $T_{cr}=(4.2\pm 0.3$)K for $B_{cr}=(0.12\pm 0.03)$ T. At that point the intermediate phase, previously described as an unstable Shastry-Sutherland phase, is suppressed. A detailed analysis around the critical point reveals a structure in the maximum of the $\partial M/\partial B(B)$ derivative which could be related to the formation of a novel phase in that critical region.