Open AccessGeneration of sequences of strong electric monopulses in nitride films
Author(s) -
V. Grimalsky,
Svetlana Koshevay,
J. Escobedo-Alatorre,
A. Kotsarenko
Publication year - 2021
Publication title -
facta universitatis. series electronics and energetics/facta universitatis. series: electronics and energetics
Language(s) - English
Resource type - Journals
eISSN - 2217-5997
pISSN - 0353-3670
DOI - 10.2298/fuee2102187g
Subject(s) - electric field , excited state , materials science , doping , microwave , conductivity , amplitude , condensed matter physics , envelope (radar) , nonlinear system , optoelectronics , nitride , electrical resistivity and conductivity , space charge , semiconductor , atomic physics , optics , physics , telecommunications , nanotechnology , electron , layer (electronics) , quantum mechanics , radar , computer science
This paper presents theoretical investigation of the excitation of the sequences of strong nonlinear monopulses of space charge waves from input small envelope pulses with microwave carrier frequencies due to the negative differential conductivity in n-GaN and n-InN films. The stable numerical algorithms have been used for nonlinear 3D simulations. The sequences of the monopulses of the strong electric field of 3 - 10 ps durations each can be excited. The bias electric field should be chosen slightly higher than the threshold values for observing the negative differential conductivity. The doping levels should be moderate 1016 -1017 cm-3in the films of ? 2 mm thicknesses. The input microwave carrier frequencies of the exciting pulses of small amplitudes are up to 30 GHz in n-GaN films, whereas in n-InN films they are lower, up to 20 GHz. The sequences of the electric monopulses of high peak values are excited both in the uniform nitride films and in films with non-uniform conductivity. These nonlinear monopulses in the films differ from the domains of strong electric fields in the bulk semiconductors. In the films with non-uniform doping the nonlinear pulses are excited due to the inhomogeneity of the electric field near the input end of the film and the output nonlinear pulses are rather domains.