Electrical Transport at high pressures of Cr3Te4 ferromagnet

PEDRAZZINI, P.; FRANCO, D.; NIEVA, G.; JACCARD, D.; PRISTÁS, G.; GABÁNI, S.

S.C. de Bariloche

Conferencia; Advanced Topics of Magnetism and Superconductivity (AToMS-2014); 2014

Centro Atomico Bariloche (CNEA) e Instituto Balseiro (CNEA-UNCuyo)

The chromium chalcogenide Cr3Te4 orders ferromagnetically at TC~325 K, displaying a slight moment rearrangement at TN~80 K. Although the pressure effect on both transitions has been studied through transport, thermodynamic and spectroscopic techniques, there is still room for different interpretations on the evolution of magnetism. We show high pressure electrical resistivity r(T) and thermoelectric power S(T ) measurements on single crystals performed inside liquid (0 < p < 2.5 GPa) and solid (0 < p <8.5 GPa) media. We detect a possible tricritical point around p1 ≥ 2.2 GPa, where TC(p) and TN(p) seem to coincide. At pressures above p2~3.5 GPa we observe a change in the r(T) curves: the magnetic transition anomaly can no longer be detected, while the residual resistivity r0(p) and thermopower coefficient S0(p) = S(T,p)/T display a sudden discontinuity. The electrical resistivity of Cr3Te4 is non-metallic at pressures p>p2. We will discuss different alternatives that can explain these changes with applied pressures.