Ferromagnetic order in Yb(Rh$_{0.73}$Co$_{0.27}$)$_{2}$Si$_{2}$

TL;DR

This paper reports the discovery of ferromagnetic order in a specific ytterbium-based compound, revealing new magnetic behavior that prompts further investigation into related materials and conditions.

Contribution

It presents the first observation of ferromagnetism in Yb(Rh$_{0.73}$Co$_{0.27}$)$_{2}$Si$_{2}$, expanding understanding of magnetic phases in this family of compounds.

Findings

Ferromagnetic order below 1.30 K with a magnetic moment of 0.1 μ_B/Yb.

Large c-axis susceptibility peak indicating ferromagnetism.

Hysteresis in magnetization confirming spontaneous magnetic order.

Abstract

We present the discovery of ferromagnetism in single crystalline Yb(Rh$_{0.73}$Co$_{0.27}$)$_{2}$Si$_{2}$ below $T_{C} = 1.30\,$K with a spontaneous magnetic moment of $0.1\,\mu_{B}$/Yb along the crystallographic c-axis. This is shown by the huge c-susceptibility peak, the hysteresis in magnetization as well as by the field-dependent susceptibility and specific heat data. This discovery motivates the reinvestigation of the magnetic order in Yb(Rh$_{1-x}$Co$_{x}$)$_{2}$Si$_{2}$ with $x < 0.27$ and in pure YbRh$_{2}$Si$_{2}$ under small pressures with field along the $c$-direction to look for low-lying ferromagnetic order.