Physics – Condensed Matter – Mesoscale and Nanoscale Physics
Scientific paper
2008-07-04
Phys. Rev. B 78, 155313 (2008)
Physics
Condensed Matter
Mesoscale and Nanoscale Physics
16 pages, 12 figures
Scientific paper
10.1103/PhysRevB.78.155313
Recently, we have found an additional spin-orbit (SO) interaction in quantum wells with two subbands [Phys. Rev. Lett. 99, 076603 (2007)]. This new SO term is non-zero even in symmetric geometries, as it arises from the intersubband coupling between confined states of distinct parities, and its strength is comparable to that of the ordinary Rashba. Starting from the $8 \times 8$ Kane model, here we present a detailed derivation of this new SO Hamiltonian and the corresponding SO coupling. In addition, within the self-consistent Hartree approximation, we calculate the strength of this new SO coupling for realistic symmetric modulation-doped wells with two subbands. We consider gated structures with either a constant areal electron density or a constant chemical potential. In the parameter range studied, both models give similar results. By considering the effects of an external applied bias, which breaks the structural inversion symmetry of the wells, we also calculate the strength of the resulting induced Rashba couplings within each subband. Interestingly, we find that for double wells the Rashba couplings for the first and second subbands interchange signs abruptly across the zero bias, while the intersubband SO coupling exhibits a resonant behavior near this symmetric configuration. For completeness we also determine the strength of the Dresselhaus couplings and find them essentially constant as function of the applied bias.
Bernardes Esmerindo
Calsaverini Rafael S.
Egues Carlos J.
Loss Daniel
No associations
LandOfFree
Intersubband-induced spin-orbit interaction in quantum wells does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Intersubband-induced spin-orbit interaction in quantum wells, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Intersubband-induced spin-orbit interaction in quantum wells will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-598142