A story of high-temperature ferromagnetism in semiconductors

TL;DR

This review discusses the synthesis, analysis, and mechanisms of high-temperature ferromagnetism in semiconductors, highlighting nano-scale phase separations and the potential for ferromagnetism without magnetic ions.

Contribution

It provides a comprehensive overview of methods, tools, and mechanisms related to high-temperature ferromagnetism in semiconductors, including nano-analytic techniques and control of magnetic cation aggregation.

Findings

Nano-scale phase separations are crucial for ferromagnetism.

Element-specific nano-analytic tools reveal material microstructure.

Controlling magnetic cation aggregation influences ferromagnetic properties.

Abstract

The comprehensive search for multifunctional materials has resulted in the discovery of semiconductors and oxides showing ferromagnetic features persisting to room temperature. In this tutorial review the methods of synthesis of these materials, as well as the application of element-specific nano-analytic tools, particularly involving synchrotron radiation and electron microscopy, are described and shown to reveal the presence of nano-scale phase separations. Various means to control the aggregation of magnetic cations are discussed together with the mechanisms accounting for ferromagnetism of either condensed or diluted magnetic semiconductors. Finally, the question of whether high temperature ferromagnetism is possible in semiconductors not containing magnetic ions is touched upon.