An origin behind Rashba spin splitting within inverted doped sGe heterostructures

In this paper, we demonstrate why cubic Rashba spin splitting is observed within inverted doped strained germanium (sGe) hetrostructures. Magnetotransport measurements showed beating within the SdH oscillation, with fast Fourier analysis revealing cubic Rashba spin splitting to be present. A cubic Rashba coefficient of beta = 7.97 x 10(-29) eVm(3) and a spin-splitting energy of Delta = 1.17 meV were determined. The source of the cubic Rashba spin splitting was identified from a combination of ultra low energy secondary ion mass spectrometry analysis and subsequent band structure modelling using Nextnano(3). Ultra-low energy secondary ion mass spectrometry revealed an unintentional, highly B doped near surface region accounted for structure inversion asymmetry, whereas subsequent band structure modelling using Nextnano(3) demonstrates how this asymmetric B doping generates structural inversion asymmetry within the sGe QW structure and cubic Rashba spin splitting realized. Published by AIP Publishing.