title: Room-temperature continuous-wave operation of an external-cavity quantum cascade laser.
abstract: Room-temperature, continuous-wave operation of an external-cavity quantum cascade laser (EC-QCL) is reported. Single-mode tuning range of 120 cm(-1) was achieved, from 7.96 to 8.84 microm. The gain chips utilized are based on the bound to continuum design and were fabricated as buried heterostructure lasers. Gap-free tuning (mode hops only on the external-cavity modes) is demonstrated for an antireflection-coated laser, just by grating rotation. The EC-QCL was implemented in a Littrow setup and an average power of 1.5 mW was obtained at 20 degrees C, while a peak power of 20 mW was obtained for a modified Littrow setup with the back extraction of light.
authors.affiliation: Ecole Polytechnique Fédérale de Lausanne, Laboratory of Physics of Nanostructures, Switzerland. arun.mohan@epfl.ch
authors.forename: Arun
authors.initials: A
authors.lastname: Mohan
authors.forename: Andreas
authors.initials: A
authors.lastname: Wittmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Hugi
authors.forename: Stéphane
authors.initials: S
authors.lastname: Blaser
authors.forename: Marcella
authors.initials: M
authors.lastname: Giovannini
authors.forename: Jérôme
authors.initials: J
authors.lastname: Faist