The Rashba effect is one of the most striking manifestations of spin-orbit coupling in solids, and provides a cornerstone for the burgeoning field of semiconductor spintronics. It is typically assumed to manifest as a momentum-dependent splitting of a single initially spin-degenerate band into two branches with opposite spin polarisation. Here, combining polarisation-dependent and resonant angle-resolved photoemission measurements with density-functional theory calculations, we show that the two "spin-split" branches of the model giant Rashba system BiTeI additionally develop disparate orbital textures, each of which is coupled to a distinct spin configuration. This necessitates a re-interpretation of spin splitting in Rashba-like systems, and opens new possibilities for controlling spin polarisation through the orbital sector.
@article{arxiv.1507.08588,
title = {Hierarchical spin-orbital polarisation of a giant Rashba system},
author = {L. Bawden and J. M. Riley and C. H. Kim and R. Sankar and E. J. Monkman and D. E. Shai and H. I. Wei and E. Lochocki and J. W. Wells and W. Meevasana and T. K. Kim and M. Hoesch and Y. Ohtsubo and P. Le Fèvre and C. J. Fennie and K. M. Shen and F. C. Chou and P. D. C. King},
journal= {arXiv preprint arXiv:1507.08588},
year = {2015}
}
Comments
11 pages including supplemental figures, accepted for publication at Science Advances