Low-threshold lasing by merging optical BICs | Mr. Kirill Koshelev
Optical Seminar at The Department of Physics & Engineering, ITMO | 9 Jul 2021
Timecodes are below the abstract.
Mr. Kirill Koshelev,
ITMO University
Australian National University
Title: "Low-threshold lasing by merging optical BICs"
Wavelength-scale lasers provide promising applications through low power consumption requiring for optical cavities with increased quality factors. Cavity radiative losses can be suppressed strongly in the regime of optical bound states in the continuum (BICs); however, a finite size of the resonator limits the performance of BICs as cavity modes for active nanophotonic devices. Here, we employ the concept of a super-BIC mode created by merging
symmetry-protected and accidental BICs in the momentum space, and realize an efficient laser based on a finite-size cavity with a small footprint. We trace the evolution of lasing properties before and after the merging point by varying the lattice spacing, and we reveal that the super-BIC laser demonstrates the significantly reduced threshold, substantially increased quality factor, and shrunken far-field images.
0:00:00 INTRO
0:00:09 Start of the talk
00:00:50 Meta-optics overview
00:02:15 Outline
00:02:46 BIC phenomena
00:07:15 Q1:Which QF should be grater:for a symetry protected one or for an accidental bound state in the continuum when the system has looses?
00:07:50 BIC in real metamaterials
00:08:50 Lasing with BICs
00:10:50 Super BIC
00:16:26 Lasing with super-BICs
00:21:00 Technical issue
00:21:50 Q2: What caused the QF increasing (in the current research)?
00:23:05 Q3: Graph description
00:30:00 BIC lasing (a comparison table)
00:31:27 Summary
00:32:40 Acknoledgements
00:33:00 Discussion
00:46:10 End
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