Solid state defect emitters with no electrical activity

TL;DR

This paper identifies a class of point defects in 4H silicon carbide that are optically active but do not affect the electrical conductivity, challenging previous assumptions about defect behavior in semiconductors.

Contribution

The study reveals a new class of defect emitters that are optically active yet electrically inactive, providing insights into defect properties in semiconductors.

Findings

Identified defect in 4H silicon carbide that is optically active but electrically inactive

Challenged the assumption that all defect emitters alter electrical conductivity

Provided new understanding of defect states in semiconductors

Abstract

Point defects may introduce defect levels into the fundamental band gap of the host semiconductors that alter the electrical properties of the material. As a consequence, the in-gap defect levels and states automatically lower the threshold energy of optical excitation associated with the optical gap of the host semiconductor. It is, therefore, a common assumption that solid state defect emitters in semiconductors ultimately alter the conductivity of the host. Here we demonstrate on a particular defect in 4H silicon carbide that a yet unrecognized class of point defects exists which are optically active but electrically inactive in the ground state.