Millimeter-long fiber Fabry-Perot cavities

Konstantin Ott (1, 2) , Sebastien Garcia (1) , Ralf Kohlhaas (2) , Klemens Schüppert (3) , Peter Rosenbusch (2) , Romain Long (1) , Jakob Reichel (1)

1 LKB (Jussieu) - Laboratoire Kastler Brossel
2 LNE - SYRTE - Laboratoire national de métrologie et d'essais - Systèmes de Référence Temps-Espace
3 Universität Innsbruck [Innsbruck]

We demonstrate fiber Fabry-Perot (FFP) cavities with concave mirrors that can be operated at cavity lengths as large as 1.5 mm without significant deterioration of the finesse. This is achieved by using a laser dot machining technique to shape spherical mirrors with ultralow roughness and employing single-mode fibers with large mode area for good mode matching to the cavity. Additionally, in contrast to previous FFPs, these cavities can be used over an octave-spanning frequency range with adequate coatings. We also show directly that shape deviations caused by the fiber's index profile lead to a finesse decrease as observed in earlier attempts to build long FFP cavities, and show a way to overcome this problem.

Domaines: Optique [physics.optics]

Konstantin Ott, Sebastien Garcia, Ralf Kohlhaas, Klemens Schüppert, Peter Rosenbusch, et al.. Millimeter-long fiber Fabry-Perot cavities. Optics Express, 2016, 24 (9), pp.9839-9853. ⟨10.1364/OE.24.009839⟩. ⟨hal-01323860⟩