# Kondo lattice heavy fermion behavior in CeRh2Ga2

## TL;DR

This study investigates CeRh2Ga2, revealing it as a moderate heavy fermion Kondo lattice with no magnetic order down to 1.8 K, and identifies a phase transition near 255 K through various physical property measurements.

## Contribution

It provides the first comprehensive physical property characterization of CeRh2Ga2, establishing its Kondo lattice behavior and heavy fermion nature with detailed thermodynamic and transport data.

## Key findings

- CeRh2Ga2 is a paramagnetic Kondo lattice with Ce^3+ ions.
- The compound exhibits heavy fermion behavior with a high Sommerfeld coefficient.
- A phase transition occurs near 255 K, affecting its thermal and electrical properties.

## Abstract

The physical properties of an intermetallic compound CeRh2Ga2 have been investigated by magnetic susceptibility \chi(T), isothermal magnetization M(H), heat capacity C_p(T), electrical resistivity \rho(T), thermal conductivity \kappa(T) and thermopower S(T) measurements. CeRh2Ga2 is found to crystallize with CaBe2Ge2-type primitive tetragonal structure (space group P4/nmm). No evidence of long range magnetic order is seen down to 1.8 K. The \chi(T) data show paramagnetic behavior with an effective moment \mu_eff ~ 2.5 \mu_B/Ce indicating Ce^3+ valence state of Ce ions. The \rho(T) data exhibit Kondo lattice behavior with a metallic ground state. The low-T C_p(T) data yield an enhanced Sommerfeld coefficient \gamma = 130(2) mJ/mol K^2 characterizing CeRh2Ga2 as a moderate heavy fermion system. The high-T C_p(T) and \rho(T) show an anomaly near 255 K, reflecting a phase transition. The \kappa(T) suggests phonon dominated thermal transport with considerably higher values of Lorenz number L(T) compared to the theoretical Sommerfeld value L_0.