Stimuli-assisted magnetism in two-dimensional (2D) magnets*

Magnetic phase control and room temperature magnetic stability in two-dimensional (2D) materials are indispensable for realising advanced spintronic and magneto-electronic functions. Our current work employs first-principles calculations to comprehensively study the magnetic behaviour in several 2D intrinsically magnetic systems, uncovering the impact of strain and electric field on the material. Our studies have revealed that uniaxial strain leads to the feasibility of room temperature ferromagnetism in the 2D-oxychloride system and also detected the occurrence of a ferromagnetic - antiferromagnetic phase transition in the system, which is anisotropic along the armchair and zigzag directions. Beyond such a strain effect, the coupling of strain and electric field leads to a remarkable enhancement of the Curie temperature (Tc) ~ 450 K in CrOCl [1, 2]. Furthermore, the current-voltage (I–V) response showed spin-resolved conductance with 100% spin filtering, and conductance fluctuations, characterised by peak-to-valley ratio and switching efficiency offering high strain-assisted tunability [3]. These predictions based on our detailed simulations show the prospect of multi-stimuli magnetic phase control, which could have great significance for realizing magneto-mechanical sensors.

Ref:

(1)  Nair, A. K., Shivani Rani, M. Venkata Kamalakar, and Soumya Jyoti Ray. "Bi-stimuli assisted engineering and control of magnetic phase in monolayer CrOCl." Physical  Chemistry Chemical Physics 22, no. 22 (2020): 12806-12813.

(2)Kar, S., S. Rani, and S. J. Ray. "Stimuli assisted electronic, magnetic and optical phase control in CrOBr monolayer." Physica E: Low-dimensional Systems and Nanostructures 143 (2022): 115332.

(3)Rani, Shivani, A. K. Nair, M. Venkata Kamalakar, and Soumya Jyoti Ray. "Spin-selective response tunability in two-dimensional nanomagnet." Journal of Physics: Condensed Matter 32, no. 41 (2020): 415301.