2015/10/22 by Matthew A. Norcia, James K. Thompson · 1 citation
Physics and Astronomy · #Atomic and Subatomic Physics Research #Coherence (philosophical gambling strategy) #Coherence time #Cold Atom Physics and Bose-Einstein Condensates #Injection seeder #Laser #Laser linewidth #Optical cavity #Quantum optics and atomic interactions #Resonator #Spectral line #physics.atom-ph
paper · pdf · doi:10.1103/physrevx.6.011025
published as Phys. Rev. X 6, 011025 (2016) · 5 pages, 4 figures
arxiv created 2015/10/22 · openalex publication_date 2016/03/09 · arxiv updated 2016/03/23 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Today's narrowest linewidth lasers are limited by mirror motion in the reference optical resonator used to stabilize the laser's frequency. Recent proposals suggest that superradiant lasers based on narrow dipoleforbidden transitions in cold alkaline earth atoms could offer a way around this limitation. Such lasers operating on transitions with linewidth of order mHz are predicted to achieve output spectra orders of magnitude narrower than any currently existing laser. As a step towards this goal, we demonstrate and study a laser based on the 7.5-kHz linewidth dipole-forbidden 3 P 1 to 1 S 0 transition in laser-cooled and tightly confined 88 Sr. We can operate this laser in the bad-cavity or superradiant regime, where coherence is primarily stored in the atoms, or continuously tune to the more conventional good-cavity regime, where coherence is primarily stored in the light field. We show that the cold-atom gain medium can be repumped to achieve quasi-steady-state lasing. We also demonstrate up to an order of magnitude suppression in the sensitivity of laser frequency to changes in cavity length, verifying a key feature of the proposed narrow linewidth lasers.