Single crystal growth and physical property characterizations of mixed valent compound YbFe$_2$Al$_{10}$

TL;DR

This study reports the growth of single crystals of YbFe₂Al₁₀ and characterizes their physical properties, revealing mixed valence behavior, hybridization gaps, and differences from polycrystal samples.

Contribution

First detailed single crystal growth and physical property analysis of YbFe₂Al₁₀, highlighting hybridization effects and valence characteristics.

Findings

Mixed valence behavior with moderate mass enhancement

Formation of multiple hybridization energy gaps at low temperature

Differences from previous polycrystal studies

Abstract

We report single crystal growth and physical properties characterization of YbFe$_2$Al$_{10}$ compounds. The measurements of resistivity, magnetic susceptibility, and specific heat show different behaviors from previous studies on polycrystal samples. A mixed valent characteristic with moderate mass enhancement is indicated. In particular, the optical spectroscopy measurement reveals formation of multiple hybridization energy gaps which become progressively pronounced at low temperature. The multiple hybridization energy gaps are likely caused by the hybridizations between the flat band from Yb 4$f$ electrons and different bands of conduction electrons.