Ferromagnetic TM2BC (TM = Cr, Mn) monolayers for spintronic devices with high Curie temperature
PHYSICAL CHEMISTRY CHEMICAL PHYSICS, vol.23, no.10, pp.6107-6115, 2021 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 23 Issue: 10
- Publication Date: 2021
- Doi Number: 10.1039/d0cp05802e
- Journal Name: PHYSICAL CHEMISTRY CHEMICAL PHYSICS
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, EMBASE, INSPEC, MEDLINE
- Page Numbers: pp.6107-6115
- Dokuz Eylül University Affiliated: Yes
Abstract
Transition metal boro-carbide (TM2BC) structures crystallize in the layered orthorhombic structure in their bulk phases. In this study, however, we find that TM2BC (TM = Cr, Mn) prefer a tetragonal (t) crystal structure in their monolayer phases due to the occurrence of strong sp(2) bonds between the metal and B/C atoms instead of sp(3) + sp(2) bonds which exist in the orthorhombic phase. The calculated energy difference between the orthorhombic and the tetragonal structures based on density functional theory (DFT) is more than 1 eV per unit cell. In addition, t-Cr2BC and t-Mn2BC monolayers are dynamically and thermally stable with their magnetic metal electronic structures. For further investigations, we combine our DFT calculations with the Monte Carlo simulations and find that both t-TM2BC monolayers show ferromagnetic properties. The calculated Curie temperatures are 846 K and 128 K for t-Cr2BC and t-MnBC sheets, respectively. In addition, we examine the magnetic anisotropy energies (MAE) of t-TM2BC monolayers and find that both structures prefer out-of-plane as the easy axis magnetization direction and the applied electric field can easily modulate the MAE of the monolayers. Our theoretical calculations reveal that t-TM2BC (TM = Cr, Mn) sheets have great potential for the future design of controllable spintronic devices with their tunable MAE properties.