Laser-induced charge and spin photocurrents at BiAg${}_2$ surface: a first principles benchmark

Abstract

Here, we report first principles calculations and analysis of laser-induced photocurrents at the surface of a prototype Rashba system. By referring to Keldysh non-equilibrium formalism combined with the Wannier interpolation scheme we perform first-principles electronic structure calculations of a prototype BiAg${}_2$ surface alloy, which is a well-known material realization of the Rashba model. In addition to non-magnetic ground state situation we also study the case of in-plane magnetized BiAg${}_2$. We calculate the laser-induced charge photocurrents for the ferromagnetic case and the laser-induced spin photocurrents for both the non-magnetic and the ferromagnetic cases. Our results confirm the emergence of very large in-plane photocurrents as predicted by the Rashba model. The resulting photocurrents satisfy all the symmetry restrictions with respect to the light helicity and the magnetization direction. We provide microscopic insights into the symmetry and magnitude of the computed currents based on the ab-initio multi-band electronic structure of the system, and scrutinize the importance of resonant two-band and three-band transitions for driven currents, thereby establishing a benchmark picture of photocurrents at Rashba-like surfaces and interfaces. Our work contributes to the study of the role of the interfacial Rashba spin-orbit interaction as a mechanism for the generation of in-plane photocurrents, which are of great interest in the field of ultrafast and terahertz spintronics.

References in corpus (9)

• Super-Diffusive Spin-Transport as a Mechanism of Ultrafast Demagnetization
• Pure Spin Photocurrent in Non-centrosymmetric Crystals: Bulk Spin Photovoltaic Effect
• Ballistic and shift currents in the bulk photovoltaic effect theory
• Pure Bulk Orbital and Spin Photocurrent in Two-Dimensional Ferroelectric Materials
• Nonlinear spin Hall effect in $\mathcal{P}\mathcal{T}$-symmetric collinear magnets
• Laser-induced torques in metallic ferromagnets
• PT-symmetry enabled spin circular photogalvanic effect in antiferromagnetic insulators
• Spin photogalvanic effect in two-dimensional collinear antiferromagnets
• Photocurrents of charge and spin in single-layer Fe${}_3$GeTe${}_2$

Cited by in corpus (5)

• Spin and Orbital Magnetism by Light in Rutile Altermagnets
• Orbital Rashba effect as a platform for robust orbital photocurrents
• Ultrafast Orbital Hall Effect in Metallic Nanoribbons
• Deciphering the origin of spin current in spintronic terahertz emitters and its imprint on their electromagnetic radiation via time-dependent density functional theory
• Magnetic parity violation and parity-time-reversal-symmetric magnets