Interface involved Dresselhaus spin-orbit coupling in GaInAs/AlInAs heterostructures

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 beta(nu,u) (Gamma(u)) and cubic beta(nu,3) (Gamma(3)) contributions as well as the interface-induced term beta(nu,int) (Gamma(int)) of intrasubband (intersubband) kinds. Focusing on ordinary Al0.48In0.52As/Ga0.47In0.53As heterostructures with either one or two occupied subbands, we perform a self-consistent Poisson-Schrodinger 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 (Gamma(2)) depending on the interfacial effect and the parity of wave functions. As opposed to intersubband terms of the usual linear (Gamma(u)) and cubic (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.

Automated summary

The study focuses on exploring the interface-associated Dresselhaus spin-orbit coupling in nanostructures, finding that the interface SO term becomes intensified for heterostructures with varying interface smoothness, and the renormalized linear Dresselhaus coefficient accounting for the interfacial contribution may change sign.