High Q-contrast terahertz quantum cascade laser via bandgap-confined bound state in the continuum.

ABSTRACT: Photonic bound states in the continuum (BICs) are optical modes that remain highly localized despite co-existing with radiating waves in the continuum, attracting considerable attention for both fundamental studies and technological innovations. Conventional single-mode BIC lasers predominantly focus on maximizing the Q-factor of a specific mode, often overlooking the critical role of Q-contrast - the difference in Q-factors between the highest-Q BIC mode and competing modes - which is crucial for achieving stable single-mode lasing. In this study, we present a compact, high Q-contrast BIC laser, enabled by strategically optimizing the alignment of the TM₁ band of the core domain with the shell domain to confine the high Q-factor mode within the core. Using a quantum cascade las

SUBMITTER: Liu H 

PROVIDER: S-EPMC12552860 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature