학술논문

Azimuth-Incidence-Angle Tuned Near-Unity Nonreciprocity via Weyl Semimetal Hetero-Stack
Document Type
Periodical
Source
IEEE Photonics Technology Letters IEEE Photon. Technol. Lett. Photonics Technology Letters, IEEE. 36(6):381-384 Mar, 2024
Subject
Engineered Materials, Dielectrics and Plasmas
Photonics and Electrooptics
II-VI semiconductor materials
Zinc compounds
Absorption
Permittivity
Kirchhoff's Law
Tensors
Photonics
Nonreciprocal thermal radiation
near-unity
Weyl semimetal
Kirchhoff's law
Language
ISSN
1041-1135
1941-0174
Abstract
Nonreciprocal thermal radiation (NTR) has attracted much attention because of the great potentials in various aspects ranging from renewable energy, molecular sensing, to thermal circuitry and camouflage. To manipulate the magnitude and sign of nonreciprocity simultaneously, a trilayer fashion of Weyl semimetal (WSM)-dielectric-WSM terminated by a metallic substrate is proposed. By engineering the structural parameters, a surprising result of spectrally selective as well as azimuth-incidence-angle tuned NTR is realized. It is demonstrated that the mediated thermal emitter presents a near-unity nonreciprocity of 0.99 at the resonance of $9.24~\mu m$ , and a wide emission angle up to 85°. By changing the azimuthal angle of incidence ( $\phi $ ), nonreciprocity spectra can also be effectively manipulated, which is symmetrical with $\phi $ = 90°. The presented configuration works for a broad incidence and azimuthal angles range, consisting highly advantageous properties to diverse NTR applications.