Broadband 2.5-6 Μm Frequency Comb Source For Dual-Comb Molecular Spectroscopy

Absorption spectroscopy with frequency combs in the molecular fingerprint portion of the spectrum (2-10 μm) has great potential for trace molecular detection and in particular for such applications as monitoring of the atmosphere and medical breath analysis. Especially attractive is dual-comb Fourier transform spectroscopy where full advantage is taken of temporal and spatial coherence of frequency combs as well as of their broadband nature. The promise is high speed, broad spectral coverage, superior sensitivity, high spectral resolution, and the possibility of absolute frequency calibration of molecular resonances. Here we report a system suitable for performing dual-comb spectroscopy in the range of 2.5-6 μm and beyond. Broadband mid-IR frequency combs are obtained via a doubly-resonant near-degenerate synchronously pumped optical parametric oscillator (OPO) based on orientation-patterned GaAs (OP-GaAs) pumped by a femtosecond Tm-fiber laser at 2-μm wavelength. Low pump threshold (7 mW), high coherence, and broad instantaneous spectral coverage make this system extremely promising for spectroscopic studies

Surface-Emitting Qds Laser With A Monolithically Integrated Grating Outcoupler

Grating coupled surface emitting laser diodes were designed and fabricated from a 1270nm InAs QDs epi. The integrated outcoupler\u27s characteristics were compared with the grating simulation data. The advanced emitter\u27s performance enhanced the device applications. © 2009 OSA

Internal Wavelength Locking Of Broad Stripe Gratingcoupled Semiconductor Lasers

This paper investigates wavelength locking of broad stripe grating coupled surface emitting lasers. This approach introduces an innovative TIR-type Littrow grating for locking with comparisons it to a conventional DBR. © 2005 Optical Society of America

Internal Wavelength Locking Of Grating-Coupled Semiconductor Lasers Using Integrated On-Chip Littrow Grating

We have conceived, fabricated, and tested a semiconductor laser with an integrated wavelength locking mechanism using an out-coupling grating combined with a total internal reflection (TIR) Littrow grating. © 2005 OSA/IPRA 2005

Compact High Peak Power Mopa Assembly Based On Grating Coupled Laser Diodes

A hybrid MOPA was assembled by stacking laser diodes incorporating grating couplers. Applying subnanosecond driving pulses for both MO and flared PA, optical pulses with 130W peak power and 98psec pulsewidth were achieved. © 2006 IEEE

Multi-Bounce Dual Grating Reflector For Internal Wavelength Locking Of Laser Diodes

This paper introduces a multi-bounce scheme based on a Dual Grating Reflector concept for integrated wavelength locking of broad stripe laser diodes. Theoretical and experimental results are shown to have a line-width of less than 50 pm for a broad stripe device. © 2007 Optical Society of America

Compact Hybrid Master Oscillator Power Amplifier Based On Grating Coupled Laser Diodes

A hybrid master oscillator power amplifier (MOPA; was fabricated from vertically stacked laser diodes with integrated grating couplers. The MO incorporated a dual grating reflector providing a narrow emission spectrum of 0.2nm. Using a tapered amplifier, an output peak power of 32W in the pulse regime was achieved. © 2006 Optical Society of America

Fabrication Of Dual Grating Reflectors For High-Power Laser Diodes

A dual grating reflector is a scheme for wavelength stabilization of laser diodes. The fabrication of a dual grating reflector involves the fabrication of a grating coupler on the p-side of a laser diode and a feedback grating on the n-side of the same device. The basic theory of the dual grating reflector is presented, along with the methods used to determine the required tolerances for near optimum performance. The fabrication processes used to obtain the required tolerances needed for a dual grating reflector are presented

Massively Parallel Dual-Comb Molecular Spectroscopy With Two Phase-Locked Subharmonic Opos

We perform dual-comb spectroscopy using a pair of broadband (3.2-5.3μm) GaAs OPO frequency comb sources. Acquisition of 1M spectral points on a second time scale and simultaneous identification of an assortment of gases is demonstrated

Compact Vertically Stacked Master Oscillator Power Amplifier Based On Grating Coupled Laser Diodes

A new design of hybrid master oscillator power amplifier (MOPA) has been proposed and realized by vertically stacking laser diodes with optical coupling provided by identical in-plane integrated gratings. Low beam divergence, large emitting and input areas of the grating coupled devices simplify the assembling technique over the fabrication of MOPA devices based on edge-emitting laser diodes. The master oscillator also incorporates a dual-grating reflector providing a wavelength-selective feedback resulting in a narrow emission spectrum of 0.2 nm at a wavelength of 975.4 nm. The power amplifier is a tapered chip with two integrated grating couplers. The operational characteristics of the MOPA were evaluated in the pulse regime demonstrating an output peak power of 32 W with a total amplification factor of 9.3 dB. © 2006 IEEE