1-MHz linewidth VCSEL enabled by monolithically integrated passive cavity for high-stability chip-scale atomic clocks.

ABSTRACT: Narrow-linewidth vertical-cavity surface-emitting lasers (VCSELs) are key enablers for chip-scale atomic clocks and quantum sensors, yet conventional designs suffer from short cavity lengths and excess spontaneous emission, resulting in broad linewidths and degraded frequency stability. Here, we demonstrate a monolithically integrated VCSEL operating at the cesium D₁ line (894.6 nm) that achieves intrinsic linewidth compression to ~1 MHz, without requiring external optical feedback. This performance is enabled by embedding a passive cavity adjacent to the active region, which spatially redistributes the optical field into a low-loss region, extending photon lifetime while suppressing higher-order transverse and longitudinal modes. The resulting device exhibits robust single-mode

SUBMITTER: Tang Z 

PROVIDER: S-EPMC12852856 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature