Abstract
The development of novel and cost-effective THz emitters, with properties superior to current THz sources, is an active and important field of research. In this work, we propose and numerically demonstrate a simple yet effective approach of realizing terahertz sources working in continuous-wave form, by incorporating the new physics of bound state in the continuum (BIC) into thermal emitters. By deliberately designing the structure of slotted disk array made of high-resistivity silicon on top of a low index dielectric buffer layer supported by a conducting substrate, a quasi-BIC mode with ultra-high quality factor (∼104) can be supported. Our results reveal that the structure can operate as an efficient terahertz thermal emitter with near-unity emissivity and ultranarrow bandwidth. For example, an emitter working at 1.3914 THz with an ultranarrow linewidth less than 130 MHz, which is roughly 4 orders of magnitude smaller than that obtained from a metallic metamaterial-based thermal emitter, is shown. In addition to its high monochromaticity, this novel emitter has additional important advantages including high directionality and linear polarization, which makes it a promising candidate as the new generation of THz sources. It holds a great potential for practical applications where high spectral resolving capability is required.
Original language | American English |
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Pages (from-to) | 4035-4043 |
Number of pages | 9 |
Journal | Nanophotonics |
Volume | 10 |
Issue number | 16 |
DOIs | |
State | Published - 2 Nov 2021 |
Bibliographical note
Funding Information:Research funding: National Natural Science Foundation of China (11974221, 11974218, 91750201) and Local science and technology development project of the central government of China (No. YDZX20203700001766).
Publisher Copyright:
© 2021 Kaili Sun et al., published by De Gruyter, Berlin/Boston.
Keywords
- bound state in the continuum
- terahertz
- thermal emitter