In this Letter, we present a design strategy for the realization of electrically powered bound states in the continuum (BIC) lasers. Despite growing attention of the optics community for BICs, practical uses of BICs in an active device are still unestablished. A large index contrast and out-of-plane symmetries that aid the formation of BICs are not trivial to achieve using conventional approaches for semiconductor laser design. Here, we propose a doping scheme to circumvent this issue. We also show that the introduction of material absorption due to carriers deteriorates the quality factor of BIC modes and show that a suitable compromise between electrical conductivity and optical loss can be achieved.
Formation of quasi-bound states in the continuum in a single deformed microcavity
Bound states in the continuum (BICs) hold significant promise in manipulating electromagnetic fields and reducing losses in optical structures, leading to advancements in fundamental research and practical applications. Despite their observation in various optical systems, the behavior of BIC in whispering-gallery-modes (WGMs) optical microcavities, essential components of photonic integrated chips, has yet to be thoroughly explored. In this study, we propose and experimentally identify a robust mechanism for generating quasi-BIC in a single deformed microcavity. By introducing boundary deformations, we construct stable unidirectional radiation channels as leaking continuum shared by different resonant modes and experimentally verify their external strong mode coupling. This results in drastically suppressed leaking loss of one originally long-lived resonance, manifested as more than a threefold enhancement of its quality (
- Award ID(s):
- 2326780
- PAR ID:
- 10553058
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Photonics Research
- Volume:
- 12
- Issue:
- 11
- ISSN:
- 2327-9125
- Format(s):
- Medium: X Size: Article No. 2651
- Size(s):
- Article No. 2651
- Sponsoring Org:
- National Science Foundation
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