Physics

Photodielectric effect associated with excitation of impurity complexes $A^+ + e$ in quasi-zero-dimensional structures under conditions of 1D-dissipative tunneling in an external magnetic field

V. D. Krevchik, A. V. Razumov, M. B. Semenov

Penza State University, Penza

Abstract: Background. Currently, methods of contactless control of the dielectric properties of semiconductor nanostructures and the matrix surrounding them are of considerable interest. Optical modulation of permittivity in combination with controlled tunneling processes makes it possible to change the properties of low-dimensional structures in a targeted manner and, as a consequence, optimize the characteristics of semiconductor nanoelectronic devices. In this regard, semiconductor quantum dots tunnel-coupled to the surrounding matrix are of interest, since in such structures the formation of impurity complexes $A^+ + e$ is possible, the photoexcitation of which can lead to the photodielectric effect (PDE). The purpose of the work is to theoretically study the influence of tunnel transparency of the potential barrier on the PDE associated with the excitation of impurity complexes $A^+ + e$ in quasi-zero-dimensional structures in an external magnetic field. Materials and methods. The relative change in permittivity (RCDP) is calculated in the dipole approximation. The field dependence curves of RCDP are plotted for an InSb quantum dot. Numerical calculations and plotting were performed using the numerical mathematics systems Mathcad 14.0 and Wolfram Mathematica 10.2. Results. The dependence of the RCDP in a quasi-zero-dimensional semiconductor nanostructure on the magnitude of the external magnetic field induction and the parameters of 1D dissipative tunneling was investigated in the dipole approximation. Dichroism of PDE associated with the presence of an external magnetic field was detected. It is shown that an external magnetic field suppresses PDE, which is associated with an increase in the localization of the electron wave function in the magnetic field, as well as with a modification of the electron adiabatic potential. It is shown that the magnitude of the RCDP depends on the parameters of dissipative 1D tunneling. Conclusions. In a magnetic field, effective control of the PDE is possible by modifying the electron adiabatic potential and the electron wave function by varying the parameters of dissipative tunneling.

Keywords: photodielectric effect, magnetic field, quantum dot, adiabatic approximation, impurity complex, relative permittivity, 1D-dissipative tunneling, electron adiabatic potential, quasi-zero-dimensional structure

UDC: 539.23

DOI: 10.21685/2072-3040-2025-2-10