title: Sub-kHz lasing of a CaF₂ whispering gallery mode resonator stabilized fiber ring laser.
abstract: We utilize a high quality calcium fluoride whispering-gallery-mode resonator to passively stabilize a simple erbium doped fiber ring laser with an emission frequency of 196THz (wavelength 1530nm) to an instantaneous linewidth below 650Hz. This corresponds to a relative stability of 3.3 × 10(-12) over 16μs. In order to characterize the linewidth we use two identical self-built lasers and a commercial laser to determine the individual lasing linewidth via the three-cornered-hat method. We further show that the lasers are finely tunable throughout the erbium gain region.
authors.forename: M C
authors.initials: MC
authors.lastname: Collodo
authors.forename: F
authors.initials: F
authors.lastname: Sedlmeir
authors.forename: B
authors.initials: B
authors.lastname: Sprenger
authors.forename: S
authors.initials: S
authors.lastname: Svitlov
authors.forename: L J
authors.initials: LJ
authors.lastname: Wang
authors.forename: H G L
authors.initials: HG
authors.lastname: Schwefel