1. Forschung
  2. Publikationen
  3. Compact, Watt-class 785 nm dua ...

Publikationen

Compact, Watt-class 785 nm dual-wavelength master oscillator power amplifiers

A. Müller, M. Maiwald and B. Sumpf

Published in:

J. Phys. Commun., vol. 6, no. 12, pp. 125007, doi:10.1088/2399-6528/acac6e (2022).

Abstract:

785 nm micro-integrated, dual-wavelength master oscillator power amplifiers with a footprint of 5 mm × 25 mm are presented. They are based on Y-branch distributed Bragg reflector ridge waveguide diode lasers and anti-reflection coated tapered amplifiers. In order to reduce the impact of potential optical feedback, devices with master oscillator front facet reflectivities of 5% and 30% as well as with an integrated miniaturized optical isolator have been realized. A comparison up to 1 W shows narrowband dual wavelength laser emission with a spectral distance of 0.6 nm (10 cm−1) and individual spectral widths<20 pm. As expected, a higher front facet reflectivity leads to a significant reduction of feedback related mode hops. Longitudinal modes corresponding to the master oscillator resonator length remain within spectral windows <0.15 nm (3 cm−1), suitable for applications such as Raman spectroscopy and especially shifted excitation Raman difference spectroscopy. Integrating a compact 30 dB optical isolator completely eliminates the observed optical feedback effects. Lateral beam propagation ratios of 1.2 (1/e2) enable easy beam shaping and fiber coupling. Outside of the experimental comparison, the developed MOPAs provide up to 2.7 W of optical output power available for applications.

Ferdinand-Braun-Institut (FBH), Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany

Keywords:

master oscillator power amplifier, diode laser, distributed Bragg reflector, tapered amplifier, dual-wavelength, Raman spectroscopy

© 2022 The Author(s). Published by IOP Publishing Ltd
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence.
Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Full version in pdf-format.