Vol. 16, no.1, 2024
РусскийEnglish
NANOSYSTEMS
OPTIMIZATION OF OPTICAL ABSORPTION IN SPINTRONIC TERAHERTZ EMITTERS USING BRAGG REFLECTORS
Anastasiya V. Gorbatova, Arseny M. Buryakov
MIREA-Russian technological university, https://www.mirea.ru/
Moscow 119454, Russian Federation
E-mail: gorbatova@mirea.ru, buryakov@mirea.ru
Received October 21, 2023, peer-reviewed October 25, 2023, accepted October 31, 2023, published March 15, 2024.
Abstract: An optimized design of a spintronic terahertz emitter has been developed, based on a bilayer Co/Pt structure with an integrated distributed Bragg reflector. The incorporation of the Bragg mirror between the Co/Pt structure and the silicon substrate enhances optical absorption in the ferromagnetic layer, thereby amplifying spin current generation and, consequently, THz signal. A model was developed for calculating the optical absorption in the ferromagnetic layer of the spintronic emitter, taking into account the parameters of the Bragg mirror (layer thicknesses, period) based on the superlattice structure [TiO2/SiO2]N. This model is grounded on the solution of Maxwell's equations for electromagnetic waves using the COMSOL Multiphysics software. The effect of anti-reflective dielectric coatings on the level of optical absorption in the ferromagnetic layer was also analyzed. The study confirmed that using the optimized Bragg mirror is sufficient for achieving optimal absorption.
Keywords: terahertz radiation, spintronic emitter, Bragg mirror, anti-reflection coating, Fabry-Perot cavity, COMSOL Multiphysics
UDC 535.34, 537.9
RENSIT, 2024, 16(1):101-110e DOI: 10.17725/j.rensit.2024.16.101
Full-text electronic version of this article - web site http://en.rensit.ru/vypuski/article/536/16(1)101-110e.pdf