Tunable band gap and enhanced ferromagnetism by surface adsorption in monolayer Cr2Ge2Te6

• Verfasst von: Song, Changsheng [VerfasserIn]
• Verfasst von: Lu, Yi [VerfasserIn]
• Titel: Tunable band gap and enhanced ferromagnetism by surface adsorption in monolayer Cr2Ge2Te6
• Verf.angabe: Changsheng Song, Wen Xiao, Lei Li, Yi Lu, Peiheng Jiang, Chaorong Li, Aixi Chen, and Zhicheng Zhong
• E-Jahr: 2019
• Jahr: 25 June 2019
• Umfang: 5 S.
• Fussnoten: Gesehen am 06.08.2019 ; Im Titel ist "2" und "6" tiefgestellt
• Titel Quelle: Enthalten in: Physical review
• Ort Quelle: Woodbury, NY : Inst., 2016
• Jahr Quelle: 2019
• Band/Heft Quelle: 99(2019,21) Artikel-Nummer 214435, 5 Seiten
• ISSN Quelle: 2469-9969
• DOI: doi:10.1103/PhysRevB.99.214435
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1670620751

Abstract

Two-dimensional (2D) van der Waals (vdW) materials have attracted significant attention for their promising applications in spintronic devices. Here, using first-principles calculations and renormalized spin-wave theory, we investigate the influence of surface adsorption (H and alkali metals) on the bandgap and ferromagnetism of monolayer Cr2Ge2Te6. We find that H-atom adsorption maintains the bandgap of Cr2Ge2Te6 around 0.95 eV but leads to a nearly indirect-to-direct band gap transition, while alkali-metal adsorption removes the bandgap and induces metallicity. More importantly, both H and alkali-metal adsorption surprisingly make the magnetic anisotropy energy four times larger than that of pristine Cr2Ge2Te6, leading to an increase of Tc by about 33%. Our findings of adsorption-controlled bandgap and magnetism in a 2D vdW magnet may open up opportunities for potential applications for new-generation magnetic memory storage, sensors, and spintronics.