# Two-channel conduction in YbPtBi

## TL;DR

This study explores the two-channel conduction mechanism in YbPtBi, revealing distinct electron and hole contributions to its transport and optical properties, with implications for understanding its charge carrier dynamics.

## Contribution

It provides a comprehensive analysis combining transport and optical measurements to model two-channel conduction in YbPtBi, highlighting the different mobilities of electrons and holes.

## Key findings

- Electrons have high mobility (~50000 cm²/Vs) at low temperatures.
- Holes exhibit low mobility (~10 cm²/Vs) and nearly constant concentration.
- Optical spectra reveal two Drude bands corresponding to different charge carriers.

## Abstract

We investigated transport, magnetotransport, and broadband optical properties of the half-Heusler compound YbPtBi. Hall measurements evidence two types of charge carriers: highly mobile electrons with a temperature-dependent concentration and low-mobile holes; their concentration stays almost constant within the investigated temperature range from 2.5 to 300 K. The optical spectra (10 meV - 2.7 eV) can be naturally decomposed into contributions from intra- and interband absorption processes, the former manifesting themselves as two Drude bands with very different scattering rates, corresponding to the charges with different mobilities. These results of the optical measurements allow us to separate the contributions from electrons and holes to the total conductivity and to implement a two-channel-conduction model for description of the magnetotransport data. In this approach, the electron and hole mobilities are found to be around 50000 and 10 cm$^{2}$/Vs at the lowest temperatures (2.5 K), respectively.