Open AccessThermal radiation of extended particles with subwavelength transverse dimensions
Author(s) -
A. N. Sviridov,
Л. Д. Сагинов
Publication year - 2021
Publication title -
prikladnaâ fizika
Language(s) - English
Resource type - Journals
ISSN - 1996-0948
DOI - 10.51368/1996-0948-2021-3-17-25
Subject(s) - transverse plane , perpendicular , physics , polarization (electrochemistry) , cutoff , wavelength , radiation , optics , transverse mode , cutoff frequency , computational physics , geometry , quantum mechanics , laser , chemistry , mathematics , structural engineering , engineering
The paper proposes a new method for calculating the integral and spectral radiation coeffi-cients of extended subwavelength particles (ESPs), which include micro and nanocylinders and parallelepipeds. Comparison of the results of calculations by the proposed method with the calculated and experimental data found in the literature is carried out. It is shown that with decrease in only the transverse dimensions of the ESP (from values much larger than λmax to values much smaller than max) from the radiation spectrum, which was originally de-scribed by Planck's law and contained modes with both polarization directed along the axis and with polarization directed perpendicular to the axis , modes with wavelengths exceeding λcutoff (λcutoff is the cutoff wavelength) and having polarization perpendicular to the longi-tudinal axis of the ESP will be gradually eliminated, while modes with wavelengths polarized along the ESP axis will always be present in the radiation spectrum of the ESP. When the transverse dimensions of the ESP become much less than λmax, then all modes with polariza-tion perpendicular to the axis will disappear from the emission spectrum of this ESP, and on-ly modes with longitudinal polarization will remain. This is a fundamental difference from the SPs considered earlier in [16, 17], where methods for calculating SPs as disks, spheres, cubes were proposed. All the proposed calculation methods use the formalism of the decom-position of radiation fluxes into spectral-spatial modes.