Strain-tunable magnetic phase transition and magnetocaloric effect in the CrS 2 monolayer with bipolar magnetic semiconducting characteristics

作者：Liping Xu, Peng Jiang, Linlin Liu, Hongmei Huang, Yanling Li · 发表于：Physical review. B./Physical review. B · 年份：2025 · DOI：10.1103/physrevb.111.205407 · 被引用次数：10 · 研究领域：2D Materials and Applications、Magnetic and transport properties of perovskites and related materials、Heusler alloys: electronic and magnetic properties

Two-dimensional (2D) ferromagnetic materials with high-temperature intrinsic magnetic ordering, electrically tunable spin polarity, and significant magnetocaloric effect (MCE) are highly desirable for designing nanoscale spintronic devices and developing multifunctional materials. In this work, we employ first-principles calculations in conjunction with atomic spin dynamics (ASD) simulations to identify a 2D monolayer phase of ${\mathrm{CrS}}_{2}$ with space group $P\overline{4}{2}_{1}m$, exhibiting high-Curie-temperature (${T}_{\mathrm{C}}$) Ising ferromagnetism and bipolar magnetic semiconducting characteristics. The intrinsic ferromagnetism originates from the strong superexchange interactions between Cr cations mediated by S anions. Moreover, we explore its layer-dependent electronic structure and find that even-layered ${\mathrm{CrS}}_{2}$ systems exhibit altermagnetism with the momentum-dependent spin splitting. ASD simulations demonstrate that the ${\mathrm{CrS}}_{2}$ monolayer possesses an excellent MCE with the maximum magnetic entropy change $\ensuremath{-}\mathrm{\ensuremath{\Delta}}{S}_{\mathrm{M}}^{max}$ of 8.03 $\textmu{}\mathrm{J}/{\mathrm{m}}^{2}$/K, the maximum adiabatic temperature change $\mathrm{\ensuremath{\Delta}}{T}_{\mathrm{ad}}^{max}$ of 2.17 K, and a relative cooling power (RCP) of 722.70 $\textmu{}\mathrm{J}/{\mathrm{m}}^{2}$ under an out-of-plane magnetic field of 5 T. Additionally, we systematically investigate the effects of biaxial strain on its...