I.D. Lindsay

110 GHz rapid, continous tuning from an optical parametric oscillator pumped by a fiber-amplified DBR diode laser

A singly-resonant continuous-wave optical parametric oscillator (cw-OPO) pumped by a fiber-amplified diode laser is described. Tuning of the pump source allowed the OPO output to be tuned continuously, without mode-hops, over 110 GHz in 29 ms. Discontinuous pump tuning over 20 nm in the region of 3.4 microm was also obtained. The rapid and continuous idler tuning was demonstrated by the measurement of a methane absorption spectrum. We believe this to be the first example of a singly-resonant OPO pumped by a fiber-amplified diode laser and the mode-hop free tuning range to be the highest reported for a cw-OPO.

Mid-infrared wavelength- and frequency-modulation spectroscopy with a pump-modulated singly-resonant optical parametric oscillator

We describe the implementation of the wavelength- and frequency-modulation spectroscopy techniques using a singly-resonant optical parametric oscillator (OPO) pumped by a fiber-amplified diode laser. Frequency modulation of the diode laser was transferred to the OPOs mid-infrared idler output, avoiding the need for external modulation devices. This approach thus provides a means of implementing these important techniques with powerful, widely tunable, mid-infrared sources while retaining the simple, flexible modulation properties of diode lasers.

Incoherently pumped continuous wave optical parametric oscillator broadened by non-collinear phasematching

In this paper, we report on a singly resonant optical parametric oscillator (OPO) pumped by an amplified spontaneous emission (ASE) source. The pump focusing conditions allow non-collinear phasematching, which resulted in a 230 nm (190 cm(-1)) spectral bandwidth. Calculations indicate that such phasematching schemes may be used to further broaden OPO spectral bandwidths.

Singly resonant optical parametric oscillators with pump-modulation transfer for frequency modulated spectroscopy in the mid-infrared

Frequency modulation (FM) techniques are well known methods for improving signal-to-noise ratios in laser spectroscopy. Such techniques have proven particularly effective with diode lasers due to the ease with which they can be frequency modulated via their injection current. Although singly-resonant optical parametric oscillators (OPOs) are flexible, powerful and widely-tunable sources for mid-infrared laser spectroscopy, the utilization of FM techniques with OPOs suffers from the inconvenience of requiring an external mid-IR modulator. As a consequence, FM techniques have not been implemented with such devices. In this paper we describe the implementation of wavelength-modulation spectroscopy (WMS) and frequency-modulation spectroscopy (FMS) using a singly-resonant OPO pumped by a fiber-amplified diode laser. The OPO was capable of producing output powers of up to 1W in the 3.15-3.8 &mgr;m range with continuous tuning over >100GHz on millisecond timescales. Frequency modulation, via injection current, of the diode laser transferred directly to the OPOs idler output, allowing mid-IR FM to be achieved without external modulation devices. WMS and FMS spectra of methane were then recorded, clearly demonstrating that this approach provides a means of implementing these important techniques with powerful, widely tunable, mid-IR sources while retaining the simple, flexible modulation properties of diode lasers.

Spectral shaping of a 10 W diode laser-Yb-fiber amplifier system

We describe a continuous-wave master-oscillator power-amplifier system based on a distributed Bragg reflection diode laser and an Yb doped fiber amplifier. The observed optical spectrum of the amplified seed source can be tailored to arbitrary shapes and widths between 30 MHz and greater than 1 GHz by controlling the radio frequency modulation wave form of the injection current. ©2006 American Institute of Physics

Amplification of short pulses from a mode-locked diode laser in an ytterbium-doped fiber

We report the first mode-locked diode laser at 1.04 µm with subsequent amplification of the pulses in an ytterbium-doped fiber amplifier. The generated pulses have a pulse duration of 70ps and peak power of 50W.

9-Watt cw swept-wavelength diode-oscillator Yb-fiber-amplifier system

We describe a 1080-nm diode master oscillator utilizing a fiber Fabry-Perot tunable filter with subsequent fiber amplification to 9 W output power. 25 MHz linewidth and 5 THz tuning in less than 1 ms were achieved.