Spin texture and Larmor precession caused by Rashba spin–orbit interaction for holes confined in <i>quasi</i>-two dimensional silicon quantum well system: crystal face dependence

We extend the k･p perturbation approach by taking into account the Rashba spin-orbit interaction (SOI) up to those 2^nd order terms crossing with k･p term, and explore the spin texture (ST) for holes confined in the Si two-dimensional quantum well (Si 2DQW) system. The intersubband interaction (ISI) strongly modulates ST as well as the electronic structure (ES) of the heavy-mass holes (HHs), light-mass (LHs), and separate ones (SHs). We then study the Larmor precession (LP) for HHs, LHs and SHs by combining the semi-classical motion of equation with the time-dependent Schroedinger (rate) equation for the Bloch periodic part of each hole. We particularly focus on the influence by the change in crystal faces of the 2DQW system via ISI. The magnetic field applied perpendicular to the 2DQW is 47 mT, weak enough to generate LP in the simple cyclotron motion (CM).
During the single period of CM, HHs confined in Si (001) 2DQW cause the most significant spin flips (SFs) whereas HHs confined in (110) 2DQW hardly generate SFs. LHs weaken the anisotropy both in ES and ST. Nevertheless, LHs confined in (110) 2DQW somehow produces the multiple SFs during the single CM period. Contrary, SHs do not produce SFs, irrespective of the typical Si crystal faces of (001), (110) and (111).