Open AccessLow-threshold and controllable nanolaser based on quasi-BIC supported by an all-dielectric eccentric nanoring structure
Author(s) -
Weilin Bi,
Xin Zhang,
Yan Meng,
Lina Zhao,
Tingyin Ning,
Yanyan Huo
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.420001
Subject(s) - nanolaser , nanoring , lasing threshold , materials science , nanostructure , optics , optoelectronics , physics , nanotechnology , laser
High-Q factor can enhance the interaction between light and matter, which is an important parameter to decrease the threshold of nanolasers. Here, we theoretically propose an eccentric nanoring structure with a high and controllable Q factor to realize a low-threshold and controllable nanolaser by amplifying the quasi-bound states in the continuum (quasi-BIC). The designed nanostructure supports a quasi-BIC because of the symmetry protection-breaking of the nanostructure. The quasi-BIC has a very high Q factor of about 9.6×10 4 and can also be adjusted by changing structural parameters. We use the energy level diagram of the four-level two-electron system to study the lasing action of the eccentric nanoring structure. The results show that the nanolaser has a relatively low threshold of about 6.46 μJ/cm 2 . Furthermore, the lasing behavior can be tuned by controlling the structural parameters of the eccentric circular ring structure.