title: Low-loss hollow waveguide fibers for mid-infrared quantum cascade laser sensing applications.
abstract: We report on single mode optical transmission of hollow core glass waveguides (HWG) coupled with an external cavity mid-IR quantum cascade lasers (QCLs). The QCL mode results perfectly matched to the hybrid HE(11) waveguide mode and the higher losses TE-like modes have efficiently suppressed by the deposited inner dielectric coating. Optical losses down to 0.44 dB/m and output beam divergence of ~5 mrad were measured. Using a HGW fiber with internal core size of 300 µm we obtained single mode laser transmission at 10.54 µm and successful employed it in a quartz enhanced photoacoustic gas sensor setup.
authors: CNR-IFN and Dipartimento Interateneo di Fisica, Università and Politecnico di Bari, Italy. pietro.patimisco@uniba.it
authors: Pietro
authors: P
authors: Patimisco
authors: Vincenzo
authors: V
authors: Spagnolo
authors: Miriam S
authors: MS
authors: Vitiello
authors: Gaetano
authors: G
authors: Scamarcio
authors: Carlos M
authors: CM
authors: Bledt
authors: James A
authors: JA
authors: Harrington