Pulsed hybrid dual wavelength Y-branch-DFB laser - tapered amplifier system suitable for water vapor detection at 965 nm with 16 W peak power
T.N. Vua,b, A. Klehra, B. Sumpfa, T. Hoffmanna, A. Lieroa, G. Tränklea
Published in:
Proc. SPIE 9767, Photonics West, San Francisco, USA, Feb. 13-18, 97670R (2016).
Abstract:
A master oscillator power amplifier system emitting alternatingly at two neighbored wavelengths around 965 nm is presented. As master oscillator (MO) a Y-branch DFB-laser is used. The two branches, which can be individually controlled, deliver the two wavelengths needed for a differential absorption measurement of water vapor. Adjusting the current through the DFB sections, the wavelength can be adjusted with respect to the targeted either "on" or "off" resonance, respectively wavelength λon or wavelength λoff. The emission of this laser is amplified in a tapered amplifier (TA). The ridge waveguide section of the TA acts as optical gate to generate short pulses with duration of 8 ns at a repetition rate of 25 kHz, the flared section is used for further amplification to reach peak powers up to 16 W suitable for micro-LIDAR (Light Detection and Ranging). The necessary pulse current supply user a GaN-transistor based driver electronics placed close to the power amplifier (PA). The spectral properties of the emission of the MO are preserved by the PA. A spectral line width smaller than 10 pm and a side mode suppression ratio (SMSR) of 37 dB are measured. These values meet the demands for water vapor absorption measurements under atmospheric conditions.
a Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany
b Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet rd., Cau Giay, Hanoi, Vietnam
Keywords:
MOPA, ns pulse, Y-branch-DFB laser, LIDAR, DIAL, water vapor.
Copyright © 2016 COPYRIGHT SPIE--The International Society for Optical Engineering. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the SPIE.
Full version in pdf-format.