Ambipolar Property of Isolated Hydrogen in Oxide Materials Revealed by Muon

TL;DR

This paper presents a semi-quantitative model that clarifies the electronic states of muons, acting as pseudo-hydrogen, in oxide materials, bridging the gap between experimental muon data and theoretical hydrogen predictions.

Contribution

The study introduces a new semi-quantitative model that systematically explains the electronic states of muons in oxides, resolving discrepancies with first-principles calculations.

Findings

The model successfully explains muon electronic states in various oxides.

It reconciles experimental muon data with theoretical hydrogen states.

Provides a framework for understanding hydrogen behavior in semiconductors.

Abstract

The study on the electronic state of muon as pseudo-hydrogen (represented by the elemental symbol Mu) has long been appreciated as one of the few methods to experimentally access the electronic state of dilute hydrogen (H) in semiconductors and dielectrics. Meanwhile, theoretical predictions on the electronic state of H in these materials by first-principles calculations using density functional theory (DFT) do not always agree with the observed states of Mu, standing as an obstacle to integrating the findings of both Mu and H. In this paper, we provide resolution to this problem by a semi-quantitative model that enables systematic understanding of the electronic states of Mu in most oxides.