Here, we theoretically demonstrate a strategy for efficiently turning whispering-gallery-mode (WGM) responses of a subwavelength dielectric disk through their near-field couplings with common low-order electromagnetic resonances of a dielectric block. Both simulations and an analytical coupled oscillator model show that the couplings are Fano interferences between dark high-quality WGMs and bright modes of the block. The responses of a WGM in the coupled system are highly dependent on the strengths and the relative phases of the block modes, the coupling strength, and the decay rate of the WGM. The WGM responses of coupled systems can exceed that of the individual disk. In addition, such a configuration will also facilitate the excitation of WGMs by a normal incident plane wave in experiments. These results could enable new applications for enhancing light-matter interactions.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OE.500562 | DOI Listing |
Nano Lett
June 2024
School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China.
We theoretically show the asymmetric spin wave transmission in a coupled waveguide-skyrmion structure, where the skyrmion acts as an effective nanocavity allowing the whispering gallery modes for magnons. The asymmetry originates from the chiral spin wave mode localized in the circular skyrmion wall. By inputting two-tone excitations and mixing them in the skyrmion wall, we observe a unidirectional output magnon frequency comb propagating in the waveguide with a record number of teeth (>50).
View Article and Find Full Text PDFAs the field of terahertz (THz) photonics advances, we present a monolithic gallium arsenide (GaAs) disk-shaped whispering gallery mode resonator that has potential as a component in THz nonlinear optics. GaAs is a material with significant optical nonlinearity which can be enhanced when the crystal is shaped into a microdisk resonator. A 4-mm-disk-resonator was fabricated using single-point diamond turning and was characterized to obtain a quality (Q) factor of 2.
View Article and Find Full Text PDFHere, we theoretically demonstrate a strategy for efficiently turning whispering-gallery-mode (WGM) responses of a subwavelength dielectric disk through their near-field couplings with common low-order electromagnetic resonances of a dielectric block. Both simulations and an analytical coupled oscillator model show that the couplings are Fano interferences between dark high-quality WGMs and bright modes of the block. The responses of a WGM in the coupled system are highly dependent on the strengths and the relative phases of the block modes, the coupling strength, and the decay rate of the WGM.
View Article and Find Full Text PDFIn this work, we analyze the first whispering gallery mode resonator (WGMR) made from monocrystalline yttrium lithium fluoride (YLF). The disc-shaped resonator is fabricated using single-point diamond turning and exhibits a high intrinsic quality factor (Q) of 8×10. Moreover, we employ a novel, to the best of our knowledge, method based on microscopic imaging of Newton's rings through the back of a trapezoidal prism.
View Article and Find Full Text PDFSci Adv
May 2023
Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Understanding the diffusion of small molecules in polymer microsystems is of great interest in diverse fundamental and industrial research. Despite the rapidly advancing optical imaging and spectroscopic techniques, entities under investigation are usually limited to flat films or bulky samples. We demonstrate a route to in situ detection of diffusion dynamics in polymer micro-objects by means of optical whispering-gallery mode resonances.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!