Low-threshold diode-laser-pumped OPOs based on QPM materials
Although attractive as compact sources of tunable infrared radiation, optical parametric oscillators pumped directly by single-mode diode lasers require extremely low thresholds. This talk will discuss the realisation of such low-threshold devices using QPM materials.
Environmental trace gas detection using laser spectroscopy
AbstractThis special issue of Applied Physics B – Lasers and Optics attempts to document the current status and trends of environmental trace gas detection through a collection of 32 invited papers motivated in part by the need for and importance of a detailed understanding of our environment. Although numerous traditional optical methods, gas chromatography, and mass spectrometry have served us extremely well in atmospheric and environmental trace gas detection, promising new sensing and precise measurement techniques based on laser spectroscopy have emerged and been successfully used in numerous applications. The concept and timing of this special issue has been stimulated to some extent by recent exciting developments of several novel technologies, such as diode and fiber lasers for the optical communications industry, diode-pumped solid-state lasers, and novel bulk and waveguide infrared nonlinear materials. These can be applied to the ultra-sensitive, highly selective detection and real-time analysis of a large number of trace gas species by means of absorption spectroscopy in the mid-infrared “fingerprint” region, which contains virtually all the fundamental vibrational modes of molecules. Reduction of cost and complexity makes such spectroscopic sources more universally available and user friendly to both established and new fields that include air quality, atmospheric chemistry, industrial, traffic, and rural emissions, chemical analysis and process control, and medical applications.This issue, consisting of two parts, chronicles some of the most significant and representative current research trends. It is hoped that this issue will inspire new directions to both specialists and newcomers in which to drive this exciting field and envision future applications of environmental sensing.Part I: Spectroscopic air monitoring techniques and instrumentation
Tunable laser spectroscopy with near-IR diode lasers, lead salt diode lasers, and parametric frequency conversion sources
 Part II: Applications of laser- and non-laser-based spectroscopic techniques
Differential absorption lidar (DIAL) and spectroscopy (DOAS) for atmospheric researchLaser photoacoustic spectroscopyFourier transform infrared spectroscopy
 I would like to express my gratitude to excellent authors and constructive reviewers from around the world for making this issue a reality over a mere six-month period. My special thanks also go to Prof. F. Träger, Editor-in-Chief of Applied Physics B – Lasers and Optics, for providing me with the opportunity for this special issue, and to Victoria Schutter (Rice University), Gabriele Kuppstadt-Brand (University of Kassel), and Marlene Hillen (Springer-Verlag) for doing a superb job in assembling this issue.
Continuous-wave singly resonant pump-enhanced type II LiB(3)O(5) optical parametric oscillator.
We report what is to our knowledge the first demonstration of a pump-enhanced singly resonant continuous-wave optical parametric oscillator. The nonlinear material used was lithium triborate cut for noncritical phase matching along the z axis, and the device was pumped by a single-frequency argon-ion laser. The oscillation threshold was ~1.0 W at 514.5 nm. For 3.4 W of pump power, we obtained single-frequency output powers of 500 mW in the nonresonant wave, which we temperature tuned over 14 nm.