Detection of CO in air by diode-pumped 46-μm difference-frequency generation in quasi-phase-matched LiNbO_3

Abstract

Detection of CO, N(2)O, and CO(2) in ambient air was performed with a room-temperature cw IR source based on difference-frequency generation in periodically poled LiNbO(3). The source was pumped by a seeded highpower GaAlAs amplif ier at 860 nm and a diode-pumped monolithic Nd:YAG ring laser at 1064 nm. The IR output was tunable between 2160 and 2320 cm(-1) without crystal rotation. The CO detection sensitivity is extrapolated to 5 ppb m/ radicalHz if limited by IR intensity noise.

Self-, Nitrogen-, and Oxygen-Broadening Coefficient Measurements in the ν1 Band of H2O Using a Difference Frequency Generation Spectrometer at 3 μm

“…Under these conditions the idler power was about 160 nW with a conversion efficiency of 0.01%/(W · cm). This value is in agreement with other results obtained for a pump wavelength at 0.860 µm (25) and at 0.850 µm (26). The infrared beam emerging from the crystal was collimated by a CaF 2 lens with focal length 100 mm.…”

“…This technique was was first introduced by Pine (19) using cw Ar and dye lasers. More recently, the DFG technique has been demonstrated using solid state lasers in birefringent AgGaS 2 crystals (20). An important improvement has been achieved with the development of the so-called poled crystals (21), which allow a simpler phase-matching condition (22,23).…”

High Power Yb Fiber Laser With Picosecond Bursts and the Quasi-Synchronously Pumping for Efficient Midinfrared Laser Generation in Optical Parametric Oscillator

“…High power mid-infrared (IR) lasers are of great importance in the areas of environment monitoring [1], medical diagnosis [2], and counter-measurement [3]. Mid-infrared lasers with high pulse repetition rate (PRR) and ultra-short pulse durations are of special interest in many areas requiring both high average power and high peak power.…”

An all-fiber PM MOPA pumped high-power OPO at 3.82 μm based on large aperture PPMgLN

“…High power optical parametric oscillators (OPO) operating in the mid-infrared (IR) wavelength range (3-5 µm) are desirable for a wide range of applications including spectroscopy, environmental monitoring, LIDAR and missile counter-measures [1][2]. Quasi-phase-matched (QPM) OPOs based on periodically poled magnesium-oxide doped lithium niobate (PPMgLN) have moved into the mainstream of OPO research due to the large effective nonlinear coefficient, excellent power handling characteristics and wide transparency range of PPMgLN crystals [3][4][5].…”