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 β=7.97×10-29 eVm3β=7.97×10-29 eVm3 and a spin-splitting energy of Δ=1.17 meVΔ=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 Nextnano3. 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 Nextnano3 demonstrates how this asymmetric B doping generates structural inversion asymmetry within the sGe QW structure and cubic Rashba spin splitting realized. [ABSTRACT FROM AUTHOR]