tailieunhanh - Báo cáo hóa học: " Linear Rashba Model of a Hydrogenic Donor Impurity in GaAs/GaAlAs Quantum Wells"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Linear Rashba Model of a Hydrogenic Donor Impurity in GaAs/GaAlAs Quantum Wells | Nanoscale Res Lett 2009 4 178-180 DOI S11671-008-9222-5 NANO EXPRESS Linear Rashba Model of a Hydrogenic Donor Impurity in GaAs GaAlAs Quantum Wells Shu-Shen Li Jian-Bai Xia Received 8 November 2008 Accepted 19 November 2008 Published online 4 December 2008 to the authors 2008 Abstract The Rashba spin-orbit splitting of a hydrogenic donor impurity in GaAs GaAlAs quantum wells is investigated theoretically in the framework of effective-mass envelope function theory. The Rashba effect near the interface between GaAs and GaAlAs is assumed to be a linear relation with the distance from the quantum well side. We find that the splitting energy of the excited state is larger and less dependent on the position of the impurity than that of the ground state. Our results are useful for the application of Rashba spin-orbit coupling to photoelectric devices. In the framework of effective-mass envelope-function theory excluding the relativity effect the electronic states have been studied for a hydrogenic donor impurity in quantum wells QWs 1-5 and its important application in the photoelectric devices. The relativity effect introduces evidence of Rashba effects in the semiconductor materials. In recent years spin-dependent phenomena was also proposed using spin field-effect transistor based on the fact that spin precession can be controlled by an external field due to the spin-orbit interaction 6 . Gvozdic et al. studied efficient switching of Rashba spin splitting in wide modulation-doped quantum wells 7 . They demonstrated that the size of the electric-field induced Rashba spin splitting in an 80-nm wide modulation-doped InGaSb QW depends strongly on the spatial variation of the electric field. The interplay between Rashba Dresselhaus and Zeeman interactions in a QW submitted to an external magnetic field was studied by means of an accurate analytical solution of the Hamiltonian 8 . Hashimzade et al. presented a theoretical study of the electronic structure of a .