Narrow line width operation of a 980 nm gain guided tapered diode laser bar

We demonstrate two different schemes for the spectral narrowing of a 12 emitter 980 nm gain guided tapered diode laser bar. In the first scheme, a reflective grating has been used in a Littman Metcalf configuration and the wavelength of the laser emission could be narrowed down from more than 5.5 nm in the free running mode to 0.04 nm (FWHM) at an operating current of 30 A with an output power of 8 W. The spectrum was found to be tunable within a range of 16 nm. In the second scheme, a volume Bragg grating has been used to narrow the wavelength of the laser bar from over 5 nm to less than 0.2 nm with an output of 5 W at 20 A. To our knowledge, this is the first time spectral narrowing has been performed on a gain guided tapered diode laser bar. In the Littman Metcalf configuration, the spectral brightness has been increased by 86 times and in the volume Bragg grating cavity the spectral brightness has been improved over 18 times when compared to the free running operation. These schemes could be also extended for other wavelengths of interest in the future

Coherent dual-frequency emission of a vertical external-cavity semiconductor laser at the cesium D2 line

International audienceWe describe the dual-frequency and dual-polarization emission of a diode-pumped vertical external-cavity semiconductor laser at 852 nm dedicated to the coherent population trapping of cesium atoms. The output power reaches ∼20 mW on each frequency, with a frequency difference in the GHz range

Dual-frequency operation of a vertical external-cavity semiconductor laser at 852 nm

conférenceWe demonstrate the dual-­‐frequency emission of a diode-­‐pumped vertical external-­‐cavity semiconductor laser operating at 852 nm, dedicated to the coherent population trapping of cesium atoms. It is based on a single laser cavity sustaining the oscillation of two adjacent, orthogonally-­polarized, modes. Two coherent laser lines distant from a few GHz are obtained in a simple and compact configuration. Up to 20 mW has been achieved at each frequency

3.3 - 3.7µm OPO/OPA optical source for multi-species 200m range Integrated Path DIfferential Absorption Lidar

International audienceWe report on an integrated path Differential Absorption Lidar instrument based on a 3.3 - 3.7 µm range transmitter for multi-species atmospheric gas detection and quantification. Detection demonstration for atmospheric methane and water vapor is realized

Simultaneous remote monitoring of atmospheric methane and water vapor using an integrated path DIAL instrument based on a widely tunable optical parametric source

International audienceWe report on the remote sensing capability of an integrated path differential absorption lidar (IPDIAL) instrument, for multi-species gas detection and monitoring in the 3.3-3.7 µm range. This instrument is based on an optical parametric source composed of a master oscillator-power amplifier scheme--whose core building block is a nested cavity optical parametric oscillator--emitting up to 10 µJ at 3.3 µm. Optical pumping is realized with an innovative single-frequency, 2-kHz repetition rate, nanosecond microchip laser, amplified up to 200 µJ per pulse in a single-crystal fiber amplifier. Simultaneous monitoring of mean atmospheric water vapor and methane concentrations was performed over several days by use of a topographic target, and water vapor concentration measurements show good agreement compared with an in situ hygrometer measurement. Performances of the IPDIAL instrument are assessed in terms of concentration measurement uncertainties and maximum remote achievable range