Pure spin current injection of single-layer monochalcogenides. (7th March 2023)

• Record Type: Journal Article
• Authors: Mendoza, Bernardo S; Grillo, Simone; Juárez-Reyes, Lucila; Fregoso, Benjamin M
• Is Part Of: Materials research express. Volume 10:Number 3(2023)
• Publication Date: 2023-03-07
• Subjects: spin current -- 2D-monochalcogenides -- ab-initio; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/acbf99
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: We compute the spectrum of pure spin current injection in ferroelectric single-layer SnS, SnSe, GeS, and GeSe. The formalism takes into account the coherent spin dynamics of optically excited conduction states split in energy by spin–orbit coupling. The velocity of the electron's spins is calculated as a function of incoming photon energy and angle of linearly polarized light within a full electronic band structure scheme using density functional theory. We find peak speeds of 520, 360, 270 and 370 Km s −1 for SnS, SnSe, GeS and GeSe, respectively which are an order of magnitude larger than those found in bulk semiconductors, e.g., GaAs and CdSe. Interestingly, the spin velocity is almost independent of the direction of polarization of light in a range of photon energies. Our results demonstrate that single-layer SnS, SnSe, GeS and GeSe are candidates to produce on demand spin-current in spintronics applications.