Artykuł w czasopiśmie
Brak miniatury
Licencja
ClosedAccessDostęp zamknięty
 

Anomalous Rashba spin-orbit interaction in electrically controlled topological insulator based on InN/GaN quantum wells

Uproszczony widok
dc.abstract.enWe study theoretically the topological phase transition and the Rashba spin–orbit interaction in electrically biased InN/GaN quantum wells. We show that that for properly chosen widths of quantum wells and barriers, one can effectively tune the system through the topological phase transition applying an external electric field perpendicular to the QW plane. We find that in InN/GaN quantum wells with the inverted band structure, when the conduction band s-type level is below the heavy hole and light hole p-type levels, the spin splitting of the subbands decreases with increasing the amplitude of the electric field in the quantum wells, which reveals the anomalous Rashba effect. Derived effective Rashba Hamiltonians can describe the subband spin splitting only for very small wave vectors due to strong coupling between the subbands. Furthermore, we demonstrate that for InN/GaN quantum wells in a Hall bar geometry, the critical voltage for the topological phase transition depends distinctly on the width of the structure and a significant spin splitting of the edge states lying in the 2D band gap can be almost switched off by increasing the electric field in quantum wells only by a few percent. We show that the dependence of the spin splitting of the upper branch of the edge state dispersion curve on the wave vector has a threshold-like behavior with the on/off spin splitting ratio reaching two orders of magnitude for narrow Hall bars. The threshold wave vector depends weakly on the Hall bar width, whereas it increases significantly with the bias voltage due to an increase of the energetic distance between the s-type and p-type quantum well energy levels and a reduction of the coupling between the subbands.
dc.affiliationUniwersytet Warszawski
dc.contributor.authorBardyszewski, Witold
dc.contributor.authorŁepkowski, Sławomir
dc.date.accessioned2024-01-24T16:39:55Z
dc.date.available2024-01-24T16:39:55Z
dc.date.issued2017
dc.description.financeNie dotyczy
dc.description.volume29
dc.identifier.doi10.1088/1361-648X/AA6860
dc.identifier.issn0953-8984
dc.identifier.urihttps://repozytorium.uw.edu.pl//handle/item/100755
dc.languageeng
dc.pbn.affiliationphysical sciences
dc.relation.ispartofJournal of Physics Condensed Matter
dc.relation.pages195702
dc.rightsClosedAccess
dc.sciencecloudnosend
dc.titleAnomalous Rashba spin-orbit interaction in electrically controlled topological insulator based on InN/GaN quantum wells
dc.typeJournalArticle
dspace.entity.typePublication