Offset-free mid-infrared frequency comb based on a mode-locked semiconductor laser.

We demonstrate a carrier-envelope offset-free frequency comb in the mid-wavelength infrared (MWIR) based on a passively mode-locked vertical external cavity surface emitting laser (VECSEL) operating at a 1.6 GHz repetition rate. The 290 mW output spanning 3.

Low-threshold bidirectional air lasing.

Air lasing refers to the remote optical pumping of the constituents of ambient air that results in a directional laserlike emission from the pumped region. Intense current investigations of this concept are motivated by the potential applications in remote atmospheric sensing. Different approaches to air lasing are being investigated, but, so far, only the approach based on dissociation and resonant two-photon pumping of air molecules by deep-UV laser pulses has produced measurable lasing energies in real air and in the backward direction, which is of the most relevance for applications.

Optical noise of stabilized high-power single frequency optically pumped semiconductor laser.

We present a study of an actively stabilized optically pumped semiconductor laser operating single frequency at a wavelength of 1015 nm. In free running operation, the laser exhibits a single frequency output power of 15 W with a linewidth of 995 kHz for a sampling time of 1 s. The intensity and the frequency of the laser were independently stabilized to reach a laser linewidth of only 4 kHz for the same sampling time.

Narrow linewidth single-frequency terahertz source based on difference frequency generation of vertical-external-cavity source-emitting lasers in an external resonance cavity.

We demonstrate a continuous wave, single-frequency terahertz (THz) source emitting 1.9 THz. The linewidth is less than 100 kHz and the generated THz output power exceeds 100 μW.