Real-space first-principles approach to orbitronic phenomena in metallic multilayers

TL;DR

This paper introduces a real-space first-principles computational method based on density functional theory to study orbitronic phenomena in metallic multilayers, enabling detailed analysis of orbital and spin transport in complex materials.

Contribution

The authors develop a scalable, real-space DFT-based approach that incorporates disorder and finite-size effects for orbitronic phenomena in heterostructures, advancing simulation capabilities.

Findings

Substantial orbital and spin accumulation observed in transition-metal heterostructures.

Method scales linearly with system size, suitable for large complex systems.

Orbital effects emerge even in centrosymmetric systems.

Abstract

We develop a real-space first-principles method based on density functional theory to investigate orbitronic phenomena in complex materials. Using the Real-Space Linear Muffin-Tin Orbital method within the Atomic Sphere Approximation (RS-LMTO-ASA) combined with a Chebyshev polynomial expansion of the Green's functions, we compute orbital (spin) Hall transport and orbital (spin) accumulation directly in real space. The approach scales linearly with system size and naturally incorporates disorder, finite-size effects, and interface roughness. We apply the method to transition-metal-based heterostructures and demonstrate the emergence of substantial orbital (spin) accumulation, even in centrosymmetric systems. Our methodology provides a scalable and flexible framework for realistic simulations of orbital transport phenomena in complex heterostructures.