Advanced Manufacturing, Electronics and Microsystems: TechConnect Briefs 2016Advanced Manufacturing, Electronics and Microsystems TechConnect Briefs 2016

Informatics, Modeling, and Simulation Chapter 2

Resonance transmission of the electron wave through the nanofilms containing a magnetic quantum well

A.S. Sahakyan, R.M. Movsesyan, A.N. Kocharian
California State University. Los Angeles, United States

pp. 71 - 75

Keywords: magnetic diode, spin transport, resonant tunneling, low dimensional system, spin polarization, electron scattering, magnetic heterostructure

The transmission of an electron wave through so called a magnetic resonance diode is considered in semiconductor nanofilms consisting of two nonmagnetic barriers separated by a quantum (magnetic) well subjected to an external magnetic field. The system of nanofilms, known as magnetic-resonant diode allows sorting the electrons by their spin due to their resonant tunneling. The transmission coefficient through semiconductor layers was calculated, and the existence of two groups of resonant energy values, corresponding to the two different orientations of the electron spin - along the magnetic field, and against it (Zeeman splitting) was shown. At these energy values a magnetic resonant transmission of electrons is observed. In the absence of spin relaxation in the system both the tunneling transmission coefficient and the degree of spin polarization of the transmitted wave amplitude are equal one up to exponentially small terms. Increase in the number of nonmagnetic barriers and separating magnetic quantum wells leads to an increase in the number of resonance energy values for tunneling transport in each of these two groups. Earlier a controllable spin-polarized magnetic diode consisting of five semiconductor layers has been experimentally realized as a spin filtering system with the central one based on a dilute magnetic semiconductor [1]. The substances of layers have been chosen so that on the energy profile of a magnetic quantum well with the Zeeman splitting in the central layer provides spin filtering of the energy values at the resonant transmission of electrons according to the orientation of the spins in the magnetic field. [1] A. Slobodskyy, C. Gould, T. Slobodskyy, C. R. Becker, G. Schmidt, and L.W. Molenkamp, Phys. Rev. Lett., 90 246601 2003