Stability Frontiers and Mixed-dimensional physics in the Kagome Intermetallics Ln3ScBi5 (Ln = La-Nd, Sm)

TL;DR

This paper explores the stability, structure, and magnetic properties of Ln3ScBi5 kagome intermetallics, revealing how mixed-dimensional motifs influence magnetic frustration and spin dynamics, with implications for quantum states in low-dimensional physics.

Contribution

It provides a comprehensive stability assessment and uncovers the magnetic interactions and frustration mechanisms in Pr3ScBi5, a novel mixed-dimensional kagome intermetallic.

Findings

Pr3ScBi5 exhibits noncollinear AFM moments confined to Q2D kagome planes.

Strong AFM coupling occurs within Q1D zigzag chains.

Magnetic frustration involves RKKY interactions coupling conduction electrons and localized moments.

Abstract

Low-dimensional physics provides profound insights into strongly correlated interactions, leading to enhanced quantum effects and the emergence of exotic quantum states. The Ln3ScBi5 family stands out as a chemically versatile kagome platform with mixed low-dimensional structural framework and tunable physical properties. Our research initiates with a comprehensive evaluation of the currently known Ln3ScBi5 (Ln = La-Nd, Sm) materials, providing a robust methodology for assessing their stability frontiers within this system. Focusing on Pr3ScBi5, we investigate the influence of the zigzag chains of quasi-one-dimensional (Q1D) motifs and the distorted kagome layers of quasi-two-dimensional (Q2D) networks in the mixed-dimensional structure on the intricate magnetic ground states and unique spin fluctuations. Our study reveals that the noncollinear antiferromagnetic (AFM) moments of Pr3+ ions are confined within the Q2D kagome planes, displaying minimal in-plane anisotropy. In contrast, a strong AFM coupling is observed within the Q1D zigzag chains, significantly constraining spin motion. Notably, the magnetic frustration is partially the consequence of coupling to conduction electrons via the Ruderman-Kittel-Kasuya Yosida (RKKY) interaction, highlighting a promising framework for future investigations into mixed-dimensional frustration in Ln3ScBi5 systems.