Showing papers by "Jirong Yu published in 2002"
TL;DR: In this article, a single-frequency diode-pumped Ho:Tm:YLF laser was used for differential absorption lidar detection of atmospheric carbon dioxide and water vapor and for coherent detection of wind.
Abstract: We demonstrate wavelength control of a single-frequency diode-pumped Ho:Tm:YLF laser by referencing its wavelength to an absorption line of carbon dioxide We accomplish this wavelength control by injection seeding with a cw Ho:Tm:YLF laser that can be tuned over or stabilized to carbon dioxide or water vapor lines We show that the pulsed laser can be scanned precisely over an absorption line of carbon dioxide by scanning the injection seed laser wavelength We locked the pulsed laser to within 185 MHz of the absorption line center by stabilizing the injection seed on the line center The single-frequency pulsed output, intended for use as a transmitter for differential absorption lidar detection of atmospheric carbon dioxide and water vapor and for coherent detection of wind, is 100 mJ per pulse at a 5-Hz repetition rate
55 citations
09 Jan 2002
TL;DR: In this article, a diode-pumped Tm: YLF laser with 1.9µm output was reported, which is the highest energy ever reported for this laser material.
Abstract: We report on a diode pumped Tm: YLF laser generating 1.9µm output. Recently, research is being pursued to produce laser wavelength around 2µm by separating the Ho and Tm ions in different laser hosts [1,2] . Compared to co-doped laser hosts; a higher efficiency performance can be achieved by directly pumping the Holmium with a 1.9µm Tm laser due to the elimination of energy sharing between Tm and Ho as well as deleterious upconversion effects in co-doped systems. A 300-mJ Tm:YLF laser at room temperature has been demonstrated. The laser design and laser performance is described. To our knowledge, this is the highest energy ever reported for this laser material. Keywords: Lasers and laser optics, diode-pumped solid state lasers, eye-safe lasers, Rare earth and transition metal solid-state lasers, Tm doped lasers. 1. INTRODUCTION The last decade has seen a growing interest in eye-safe, high energy, efficient 2µm lasers. Applications of these lasers range from remote sensing of the atmosphere to medical and air transport safety. Atmospheric sensing lidars can benefit from high energy, eye-safe laser transmitters. The long 2µm lifetime is amenable to multiple Q-switched operations, which is ideal for DIAL application. In addition to pumping Ho laser crystals to generate the wavelength around 2 µm for lidar transmitter applications, laser sources around 1.9µm can have numerous applications in the medical field as stand-alone lasers. Tm doped YLF lasers are very attractive due to their versatility and their various transitions in the near infrared. It has been shown that by lowering the doping concentrations to avoid cross-relaxation, the 2.3µm radiation can be enhanced at the
7 citations
01 Jan 2002
TL;DR: In this article, a high energy double-pulsed Ho:Tm:YLF 2-micrometer laser amplifier has been demonstrated with the gain of 44 mJ per pulse pair under Q-switch operation.
Abstract: A high energy double-pulsed Ho:Tm:YLF 2-micrometer laser amplifier has been demonstrated 600 mJ per pulse pair under Q-switch operation is achieved with the gain of 44 This solid-state laser source can be used as lidar transmitter for multiple lidar applications such as coherent wind and carbon dioxide measurements
4 citations
03 Feb 2002
TL;DR: In this paper, Tm:Ho co-doped crystals of YLiF4 (YLF) and LuLF (LuLF) were studied for 2.0 μm laser applications.
Abstract: Tm:Ho co-doped crystals of YLiF4 (YLF) and LuLiF4 (LuLF) are studied for 2.0 μm laser applications. Energy levels and cross sections are determined for the manifolds involved in 2.0 μm lasing. Diode side-pumped laser performance shows Tm:Ho:LuLF to have a lower threshold and higher slope efficiency than Tm:Ho:YLF. An explanation for the improved performance of Tm:Ho:LuLF over Tm:Ho:YLF through modeling of the laser is presented.
3 citations
03 Feb 2002
TL;DR: In this paper, a pump-probe setup capable of directly measuring the upper laser level population dynamics of the 5I7 → 5I8 laser transition is developed taking advantage of the strong ground-state depletion.
Abstract: A pump-probe setup capable of directly measuring the upper laser level population dynamics of the 5I7 → 5I8 laser transition is developed taking advantage of the strong ground-state depletion. This pump-probe experiment first is used to investigate the spatial distribution of the pump intensity in a laser-diode side-pumped laser crystal, then to determine the main energy transfers involved in Ho:Tm systems and also to estimate the intrinsic optical losses of the laser crystal. Finally, using the results of this pumpprobe experiment we were able to precisely simulate the performance of a laser-diode side-pumped Ho:Tm YLiF4 2μm laser.
1 citations
03 Feb 2002
TL;DR: In this paper, an efficient double-pulsed Ho:Tm:YLF 2-μm laser amplifier has been demonstrated with the gain of 4.4 mJ per pulse pair under Q-switch operation.
Abstract: An efficient double-pulsed Ho:Tm:YLF 2-μm laser amplifier has been demonstrated. 600 mJ per pulse pair under Q-switch operation is achieved with the gain of 4.4, which represents the highest reported optical-to-optical efficiency at this energy level.
1 citations
24 May 2002
TL;DR: In this article, a Ho,Tm:LiYF/sub 4/2-/spl mu/m laser was developed, which operates in double pulse fashion, providing two Q-switched pulses with a single pump pulse.
Abstract: Summary from only given. We developed a Ho,Tm:LiYF/sub 4/ 2-/spl mu/m laser that operates in double pulse fashion. A unique feature of this laser is that it provides two Q-switched pulses with a single pump pulse. The oscillator and amplifier modules were both transversely pumped by GaAlAs diode lasers. Two amplifiers form a chain to provide necessary gain to the probe beam in single pass amplification.