Rashba spin–orbit interaction for holes confined in quasi-two dimensional silicon quantum well system I: Modification of spin textures

We revisit the Rashba spin–orbit interaction (SOI) for holes confined in the silicon two-dimensional quantum well (Si 2D QW) system and explore the modulation in the spin textures as well as the electronic structures. We extend the k · p perturbation approach, including possible perturbation terms crossing with the SOI couplings up to the second-order terms. Focusing on the crystal as well as the particle=atomic momenta, we explore the distribution and orientation of the effective magnetic field (EMF) caused by the SOI couplings and investigate how the EMFs change the spin textures of heavy-mass holes (HHs), light-mass holes (LHs), and separate holes (SHs). The three-fold degeneracy and finite angular momentum of j‘j ¼ 1 at the valence-band edge states cause complicated SOI couplings due to the inter-subband interaction. Consequently, holes generate the characteristic spin textures, completely different from those found in conduction electrons.