David P. Caffey

Efficient diode-array-pumped Nd:YAG and Nd:Lu:YAG lasers.

Nd:YAG (YAG) and Nd:Lu:YAG (LYAG) are investigated as high-efficiency laser materials utilizing a diode-array side-pump geometry. We demonstrate higher laser efficiencies than previously reported for transversely pumped YAG. A YAG rod yielded an optical slope efficiency of 47.7%, while a LYAG rod yielded an optical slope efficiency of 50.3%. Increased performance of these materials is attributed to higher pump absorption and lower losses.

Crystallography, spectroscopic analysis, and lasing properties of Nd 3+ :Ba 2 ZnGe 2 O 7

Nd3+:Ba2ZnGe2O7 (BZAG) is an attractive material to be pumped by laser diodes because its fluorescence lifetime is 305 μsec and it has a broad absorption centered at 806 nm. In addition, Nd3+:BZAG has a broad fluorescence spectrum and offers the potential for tunable laser output wavelengths centered at 1.05 and 1.34 μm. Time-resolved, site-selection spectroscopy measurements revealed ten different crystal-field sites for Nd3+ in BZAG, but strong energy transfer between nonequivalent ions at room temperature results in emission from only one major site. Diode-array side pumping of 5-mm-diameter rods produced optical slope efficiencies of 22.8%. Crystal structure, Judd–Ofelt analysis, and laser performance are discussed.

Diode array side-pumped neodymium-doped gadolinium scandium gallium garnet rod and slab lasers

Gadolinium scandium gallium garnet (GSGG) was studied as a high average power laser host material utilizing diode array side pumping. Maximum optical slope efficiencies of 41.5% for Nd:GSGG in the rod geometry and 32.5% for a Nd:Cr:GSGG zig‐zag slab were obtained at 1.06 μm. Nd:GSGG and Nd:YAG have similar fluorescence lifetimes while Nd:GSGG has better energy storage capabilities due to its smaller stimulated‐emission cross section.

Compact widely tunable ECqcL and its applications for gas spectroscopy

Over the past few years Daylight Solutions has introduced a family of tunable laser products tailored for scientific and OEM spectroscopic applications, ranging from gas sensing of complex matrices to condensed phase detection. The goal of this development is to create laser-based sources and instruments whose performance can rival and surpass that from conventional FTIRs. Specifically, these sources have the ability to obtain and analyze broad-band spectra in the midinfrared region with high spectral acquisition speed, perform with moderate to high spectral resolution and operate at room temperature, all while occupying minimal size and weight. This paper will report recent progress towards this goal. The performance of the novel laser capable of tuning 25% of the wavelength range centered at 8.8 um will be presented. A technology demonstration prototype employing a broadly tunable external cavity quantum cascade laser integrated into a portable, turn-key sensor will be described.

High performance results and applications of miniaturized external-cavity quantum cascade lasers (ECqcL)

Daylight Solutions has integrated commercially available quantum cascade gain media with their advanced coating and die attach technologies, mid-IR micro-optics and telecom-style assembly and packaging to yield cutting edge performance. When orchestrated together into Daylights external-cavity quantum cascade laser (ECqcL) platform, significant performance has been achieved. These ECqcL modules have now be