Electrical resistivity across the tricriticality in itinerant ferromagnet

TL;DR

This study explores how electrical resistivity changes near the tricritical point in UCo1-xRuxAl compounds, revealing phase separation, non-Fermi liquid behavior, and differences from pure UCoAl, advancing understanding of quantum phase transitions.

Contribution

It provides new experimental insights into resistivity behavior near the tricritical point in UCo1-xRuxAl, including phase separation and non-Fermi liquid characteristics, and compares these with pure UCoAl.

Findings

Phase separation confirmed at ambient pressure and 0.2 GPa.

Transition from Fermi liquid to non-Fermi liquid behavior at 0.2 GPa.

Disappearance of ferromagnetism at 0.4 GPa.

Abstract

We investigate the discontinuous ferromagnetic phase diagram near tricritical point in UCo 1-x Ru x Al compounds by electrical resistivity measurements. Separation of phases in UCo 0.995 Ru 0.005 Al at ambient pressure and in UCo 0.990 Ru 0.010 Al at pressure of 0.2 GPa and disappearance of ferromagnetism at 0.4 GPa is confirmed. The exponent of temperature dependence of electrical resistivity implies change from Fermi liquid behavior to non-Fermi liquid at 0.2 GPa and reaches minimum at 0.4 GPa. Our results are compared to results obtained on the pure UCoAl and explanation for different exponents is given.