Enhanced spin Hall conductivity and charge to spin conversion efficiency in strained orthorhombic SnSe through orbital selective hybridization

• Published in: Applied physics letters Vol. 123; no. 18
• Main Authors: Ketkar, E., Shukla, Gaurav K., Lee, Seung-Cheol, Bhattacharjee, Satadeep, Singh, Sanjay
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 30.10.2023
• Subjects: Applied physics; Charge efficiency; Compressive properties; Computer storage devices; Conduction bands; Hall effect; Memory devices; Selenium; Tantalum; Tin selenide; Transition metals; Valence band
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/5.0173339

The realization of the spin Hall effect has opened new frontiers for the design of efficient memory storage devices facilitated by the conversion of charge currents to spin currents. Here, using the Kubo formula, we calculate the intrinsic spin Hall conductivity (SHC) of orthorhombic tin selenide (o-SnSe) under the influence of isotropic compressive strain in the ab-plane. As the strain is gradually increased, we obtain a substantial hybridization between the pz orbitals of Sn and Se atoms of an electron pocket from the lowest conduction band and the topmost valence band, respectively. This hybridization process greatly enhances the SHC at the Fermi level and charge-to-spin conversion efficiency, the latter of which is superior to that of popular transition metals such as Ta and Pt. This makes strained o-SnSe an attractive candidate for use in spintronic devices.