The estimation of generation range of spin-injection THz generator

E. A. Vilkov, S. G. Chigarev
Kotelnikov Institute of Radioengineering and Electronics of RAS

The paper is received on October 20, 2016

 

Abstract. In our previous work devoted to the study of  spin–injection mechanism of  the THz- generation in magnetic junctions we established the relation between the frequency of generation and the angle between magnetizations of the contacting ferromagnetic, and also the spin polarization of the free electrons in these ferromagnetics.  It is shown that the angle between magnetizations can vary from 0 degree to 180 degree. Based on the results of previous work, we make a qualitative assessment of the possibility of multi-frequency nature of THz radiation generation in a magnetic junction of the film-rode type.  In a film-rod magnetic junction there are two possible areas of the film, in which there is radiation at two different frequencies. These are the area under the end face of the rod’s tip, where unidirectional magnetizations have different magnitudes and the area on the boundary of the rod, where multidirectional magnetizations have also different magnitudes. We make numerical assessment based on the simplified formula of the relation of radiation frequency to the directions and magnitude of magnetizations of layers. Numerical estimations are confirmed by experimental results.

Keywords: The injection of the spin via current, terahertz radiation, magnetic transition, layer magnetization, quasi-Fermi levels, radiative quantum transitions.

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