2022/07/16 by Oliver J. Clark, Oliver Dowinton, M. S. Bahramy +1 · 1 citation
Materials Science · Engineering · #2D Materials and Applications #Perovskite Materials and Applications #Quantum Dots Synthesis And Properties
paper · pdf · doi:10.1038/s41467-022-31539-2
openalex created_date 2022/07/16 · openalex publication_date 2022/07/16 · openalex updated_date 2026/07/28
Abstract Finding stimuli capable of driving an imbalance of spin-polarised electrons within a solid is the central challenge in the development of spintronic devices. However, without the aid of magnetism, routes towards this goal are highly constrained with only a few suitable pairings of compounds and driving mechanisms found to date. Here, through spin- and angle-resolved photoemission along with density functional theory, we establish how the p -derived bulk valence bands of semiconducting 1T-HfSe 2 possess a local, ground-state spin texture spatially confined within each Se-sublayer due to strong sublayer-localised electric dipoles orientated along the c -axis. This hidden spin-polarisation manifests in a ‘coupled spin-orbital texture’ with in-equivalent contributions from the constituent p -orbitals. While the overall spin-orbital texture for each Se sublayer is in strict adherence to time-reversal symmetry (TRS), spin-orbital mixing terms with net polarisations at time-reversal invariant momenta are locally maintained. These apparent TRS-breaking contributions dominate, and can be selectively tuned between with a choice of linear light polarisation, facilitating the observation of pronounced spin-polarisations at the Brillouin zone centre for all k z . We discuss the implications for the generation of spin-polarised populations from 1T-structured transition metal dichalcogenides using a fixed energy, linearly polarised light source.