# Possible devil's staircase in the Kondo lattice CeSbSe

## TL;DR

This paper investigates the complex magnetic phase diagram of CeSbSe, revealing a possible devil's staircase phenomenon linked to Kondo lattice behavior and RKKY interactions, through magnetization, heat capacity, and resistivity measurements.

## Contribution

It provides the first detailed phase diagram of CeSbSe showing a cascade of fractional magnetic states indicative of a devil's staircase, highlighting the interplay of Kondo and RKKY interactions.

## Key findings

- Observation of a cascade of magnetic phases under magnetic field.
- Evidence of Kondo lattice behavior with small charge carrier density.
- Detection of a possible devil's staircase in magnetic ordering.

## Abstract

The temperature ($T$) - magnetic field ($H$) phase diagram for the tetragonal layered compound CeSbSe, is determined from magnetization, specific heat, and electrical resistivity measurements. This system exhibits complex magnetic ordering at $T_{\rm{M}}$ $=$ 3 K and the application of a magnetic field results in a cascade of magnetically ordered states for $H$ $\lesssim$ 1.8 T which are characterized by fractional integer size steps: i.e., a possible Devil's staircase is observed. Electrical transport measurements show a weak temperature dependence and large residual resistivity which suggest a small charge carrier density and strong scattering from the $f$-moments. These features reveal Kondo lattice behavior where the $f$-moments are incompletely screened, resulting in a fine balanced magnetic interaction between different Ce neighbors that is mediated by the RKKY interaction. This produces the nearly degenerate magnetically ordered states that are accessed under an applied magnetic field.