Abstract

The interfacial effect in nanosystems is crucial for diverse fields of physics. Here we explore in detail the interface associated Dresselhaus spin-orbit (SO) coupling, which comprises the usual linear ${\ensuremath{\beta}}_{\ensuremath{\nu},\mathrm{u}}$ (${\mathrm{\ensuremath{\Gamma}}}_{\mathrm{u}}$) and cubic ${\ensuremath{\beta}}_{\ensuremath{\nu},3}$ (${\mathrm{\ensuremath{\Gamma}}}_{3}$) contributions as well as the interface-induced term ${\ensuremath{\beta}}_{\ensuremath{\nu},\mathrm{int}}$ (${\mathrm{\ensuremath{\Gamma}}}_{\mathrm{int}}$) of intrasubband (intersubband) kinds. Focusing on ordinary ${\mathrm{Al}}_{0.48}{\mathrm{In}}_{0.52}\mathrm{As}/{\mathrm{Ga}}_{0.47}{\mathrm{In}}_{0.53}\mathrm{As}$ heterostructures with either one or two occupied subbands, we perform a self-consistent Poisson-Schr\"odinger calculation to determine all the relevant SO contributions. We observe that the interface SO term becomes intensifying for heterostructures with either a weaker bulk Dresselhaus strength of the barrier layer or a lower interface smoothness. Remarkably, it is found that the renormalized linear Dresselhaus coefficient, which accounts for the interfacial contribution, may change sign as the interface smoothness varies, opening up the feasibility of the interface-engineered topological matter of persistent skyrmion lattice [J. Y. Fu, P. H. Penteado, M. O. Hachiya, D. Loss, and J. C. Egues, Phys. Rev. Lett. 117, 226401 (2016)]. Moreover, we also determine the intersubband Dresselhaus contributions including an emergent quadratic term (${\mathrm{\ensuremath{\Gamma}}}_{2}$) depending on the interfacial effect and the parity of wave functions. As opposed to intersubband terms of the usual linear (${\mathrm{\ensuremath{\Gamma}}}_{\mathrm{u}}$) and cubic (${\mathrm{\ensuremath{\Gamma}}}_{3}$) kinds, the quadratic contribution leads to unusual avoided crossings of the band dispersion and thus may hybridize spin textures of distinct spin branches. Our results should stimulate experiments probing interface-mediated intra- and intersubband Dresselhaus SO effects and provide an extra leverage for extracting reliable bulk Dresselhaus SO parameters.

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