Spin-Orbit Coupling in n-Type PbTe/PbEuTe Quantum Wells

Abstract

Magnetoresistance measurements were performed on an n-type PbTe/PbEuTe quantum well and weak antilocalization effects were observed. This indicates the presence of spin-orbit coupling phenomena and we showed that the Rashba effect is the main mechanism responsible for this spin-orbit coupling. Using the model developed by Iordanskii et al., we fitted the experimental curves and obtained the inelastic and spin-orbit scattering times. Thus we could compare the zero field energy spin-splitting predicted by the Rashba theory with the energy spin-splitting obtained from the analysis of the experimental curves. The final result confirms the theoretical prediction of strong Rashba effect on IV-VI based quantum wells.

Small Charging Energies and g-Factor Anisotropy in PbTe Quantum Dots

“…These observations point to strong Rashba spin−orbit interaction and asymmetric confinement potentials in the PbTe quantum dots. 26 This is consistent with predicted small Dresselhaus SOI in PbTe due to its inversion-symmetric rocksalt crystalline structure 38 and large Rashba SOI, as measured in PbTe quantum wells. 7 Moreover, g-factor anisotropy was predicted for [100] and [111] PbTe quantum wells, 13 where the authors included the contributions of wave function barrier penetration, confinement energy shift, and interface SO interaction in their calculations of the quantum well g-factors.…”

“…26 This is consistent with predicted small Dresselhaus SOI in PbTe due to its inversion-symmetric rocksalt crystalline structure 38 and large Rashba SOI, as measured in PbTe quantum wells. 7 Moreover, g-factor anisotropy was predicted for [100] and [111] PbTe quantum wells, 13 where the authors included the contributions of wave function barrier penetration, confinement energy shift, and interface SO interaction in their calculations of the quantum well g-factors. Furthermore, they found that a confining mesoscopic potential renormalizes the g-factor through Rashba SOI.…”

“…1−5 In this context, PbTe may offer advantages compared to more established platforms such as InSb and InAs. Work on PbTe reported large and anisotropic g-factors, with absolute values up to 58 6 and strong spin−orbit interaction (SOI); 7 both advantageous properties for the realization of sizable topological gaps at moderate magnetic fields. 8,9 PbTe, which is a well-known thermoelectric material, 10,11 also exhibits a direct band gap E g = 190 meV, 12 electron effective masses of 0.024m e − 0.24m e , 13 and a large dielectric constant ϵ r ∼ 1350 at low temperatures 12 (compared to ϵ r ∼ 14 for InAs and InSb 14 ), which is expected to result in efficient screening of impurities and, consequently, high electron mobilities.…”

Spin-dependent magneto-thermopower of narrow-gap lead chalcogenide quantum wells

“…A simple realization of this can be seen (see Fig. 3 ) by considering the minimal quadratic Hamiltonian with the linear Rashba contribution 26 where is the Rashba coefficient and determines the robustness of the splitting. The related dispersion is of the form : ε = ħ 2 k 2 /2 m * ± λ R k ; the splitting is therefore 2 λ R k , where k is the in-plane wave vector given by .…”

Electrical properties of PbTe doped with BaF2

“…Fine control of the electron density in PbTe/PbEuTe quantum wells made possible the observation of the integer quantum Hall effect 11,12 and of the conductance quantization in constricted samples. 13 The effects of localization and antilocalization were investigated in n-type 14 and p-type 15 doped Pb 1−x Eu x Te layers and an enhancement of the thermoelectric power was observed in PbTe/PbEuTe multiquantum wells. 1 In principle, the lead salts can be easily doped by controlling the stoichiometric deviation, i.e., p-type ͑n-type͒ material is obtained from a chalcogen-rich ͑metal-rich͒ growth regime.…”