The influence of temperature and impurities on the Rashba effect in a triangular quantum well

A triangular quantum well is selected as the theoretical model, and an improved linear combination operator and variational technique are employed to derive the expression for the effective mass of polarons with heavy hole characteristics in triangular quantum wells under the influence of impurities and temperature. Due to the non-centrosymmetric structure of the triangular quantum well, the effective mass of polarons undergoes Rashba spin-orbit splitting. An increase in temperature enhances the thermal excitation of phonons, intensifying hole-phonon interactions and increasing the resistance encountered by holes in lattice motion, which leads to a monotonic increase in the effective mass of polarons with temperature. The dominant role of thermally excited phonons strengthens the contribution of spin-orbit interactions to the splitting of the effective mass, manifested as an increase in the spin splitting gap with rising temperature. An increase in the Coulomb-bound potential results in a more localized hole wavefunction, amplifying the impact of the structural inversion asymmetry of the quantum well on holes. Localized holes are more susceptible to such asymmetry, which enhances the spin-orbit coupling strength and ultimately leads to an increase in the Rashba splitting gap.