Realizing half-metallicity in K sub(2)CoF sub(4) exfoliated nanosheets viadefect engineering

• Published in: Physical chemistry chemical physics : PCCP Vol. 18; no. 23; pp. 15765 - 15773
• Main Authors: Bai, Yujie, Deng, Kaiming, Kan, Erjun
• Format: Journal Article
• Language: English
• Published: 01.06.2016
• Subjects: Computer simulation; Electronics; Mathematical models; Nanostructure; Semiconductors; Strain; Two dimensional; Vacancies
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c6cp02362b

Two-dimensional (2D) materials with intriguing electronic characteristics open up tremendous opportunities for application in future nanoelectronic devices, and have become one of the hot subjects of today's research. Here, we firstly predict the possibility of realizing a 2D exfoliated ionic bonding nanosheet, namely the K sub(2)CoF sub(4) nanosheet, based on first-principles calculations. Through analysis of the cleavage energy, in-plane stiffness and stability, the free-standing K sub(2)CoF sub(4) nanosheet can be exfoliated in experiments. It is shown that the K sub(2)CoF sub(4) nanosheet with K vacancy can transform into a ferromagnetic half-metal under moderate tensile strain, whereas the pristine K sub(2)CoF sub(4) nanosheet is an antiferromagnetic semiconductor. Monte Carlo simulations based on the Heisenberg model predict that the Curie temperature for the K vacancy K sub(2)CoF sub(4) nanosheet under 2% tensile strain is higher than room temperature. Therefore, our results suggest that the K sub(2)CoF sub(4) nanosheet may be a promising material for spintronic and nanoelectronic applications.