First-principles study of d⁰ ferromagnetism in alkali-metal doped GaN

Abstract

The d0 ferromagnetism in GaN has been studied based on density functional theory. Our results show that GaN with sufficient hole become spin-polarized. Alkali-metal doping can introduce holes in GaN. Among them, both of Li- and Na-doping induce ferromagnetism in GaN and Na-doped GaN behaves as half-metallic ferromagnet. Moreover, at a growth temperature of 2000 K under N-rich condition, both concentrations can exceed 18%, which is sufficient to produce detectable macroscopic magnetism in GaN. The Curie temperature of Li- and Na-doped GaN is estimated to be 304 and 740 K, respectively, which are well above room temperature.

Regulation of the electronic properties of GaN(0001) surface by metal atoms

“…15) The d 0 ferromagnetism of alkali metal doped in GaN was investigated by Zhang. 16) Benemanskaya et al reported on the observation of photoemission from the Cs=GaN(0001) n-type interface upon the excitation of visible light in the transparent region of GaN. 17) Thus far, mainly alkali metal has been selected to affect the properties of the GaN surface, and other metals with different adsorption activities on the GaN polar surface are seldom reported.…”