Lasing characteristics of glass-fiber neodymium laser

The results of a study of the energy, temporal, and spectral characteristics of glass-fiber neodymium laser are presented. It is shown that the short-lived color centers (SCC) lead to generation of regular giant pulses, to a lowering of the superluminescence field intensity, and to an increase of the lasing efficienty in the Q-switching regime. The kinetics of the emission of a neodymium laser containing SCC in the active elements is studied. Problems encountered in obtaining a mode-locking regime in a glass-fiber laser are discussed. It is shown that the lasing spectrum consists of narrow spectral lines randomly distributed in a frequency interval up to 250–300 cm^–1.Quantum Radiophysics Division, Lebedev Physics Institute. Translated from Preprint No. 91 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1990.     

Lasing behavior of sol–gel silica doped with UV laser dyes

Received: 18 August 1997/Revised version: 18 November 1997     

Lasing characteristics of a single-frequency Tm:YAG laser

A single-frequency Tm:YAG laser at room temperature is presented. With two thin etalons as the intra-cavity tuning elements, the maximum output power 69.5 mW is obtained at room temperature. The slope efficiency is 10.2% and the optical to optical conversion efficiency of 4.02%. The central wavelength is 2012.5 nm. A temperature stability of 0.1 °C corresponds to a frequency stability of 74 MHz observed by wave meter in 50 s.     

Lasing characteristics of strongly pumped Yb-doped photonic crystal fiber laser

A strongly pumped Yb-doped large-mode-area photonic crystal fiber (LMA-PCF) laser is analyzed. The lasing characteristics of an improved Fabry-Perot (F-P) cavity fiber laser using LMA-PCF are studied theoretically based on a rate equation model and the exact numerical solution of the rate equations is in excellent agreement with the experimental result.     

Heavy-water-based solutions of rhodamine dyes: photophysical properties and laser operation

Photophysical properties of heavy-water-based rhodamine dye solutions have been investigated, with a view to assess the suitability of heavy water as a solvent for high-power, high-repetition-rate dye lasers and amplifiers. We have measured the quantum yield of fluorescence of the commonly used dyes rhodamine-6G, rhodamine-B and kiton-red, dissolved in heavy water, ethanol and normal water. The performance of a heavy-water-based pulsed rhodamine-6G dye laser has been investigated in broadband, as well as in narrowband wavelength-tunable resonator configurations, yielding laser efficiencies comparable to those achieved with ethanolic solutions of the same dye. We have also studied the thermo-optic properties of normal and heavy water, using the Z-scan technique. Finally, photodegradation rates for laser dyes have been compared in heavy water, normal water and ethanol. Our results establish heavy water as a solvent superior to both ethanol and normal water, on account of the lower thermo-optic effects and the higher photostability of rhodamine dyes when dissolved in heavy water. Received: 8 February 2002 / Published online: 8 August 2002     

Lasing in tilted-waveguide semiconductor laser amplifiers

Abstact We have observed the transition from single-pass amplification of the fundamental mode to oscillation in the higher-order modes in tilted semiconductor-based amplifiers using numerical experiments based on a novel finite-difference time-domain treatment of the optical field that includes gain. These results correlate well with laboratory observations of gain-induced oscillation in such amplifiers.     

Lasing efficiency of dyes incorporated into a nanoporous glass-polymer composite

We have used microsecond coherent pumping to study the lasing efficiency of active elements based on a nanoporous glass-polymer composite activated by organic dyes, as a function of the spectral composition of the pump within the main absorption band of the dye. We have shown that under the indicated excitation conditions, the lasing efficiency can exceed 40% and can be comparable with the lasing of liquid elements. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 5, pp. 708–716, September–October, 2008.     

Lasing characteristics and optimizations of a diode-side-pumped Tm, Ho:GdVO4 laser

A diode-pumped Tm, Ho:GdVO4 laser with a side-pumping configuration is demonstrated for the first time to our knowledge. Optimum Tm and Ho dopant concentrations for GdVO4 are somewhat lower than those for garnet and fluoride crystals. With a 3% Tm, 0.3% Ho:GdVO4 crystal an output energy of 31.2 mJ and a slope efficiency of 14.5% were obtained in normal-mode operation at room temperature.     

Lasing from an electron-beam-excited nonchain HF laser

The lasing parameters of a nonchain chemical HF laser (an active volume of 20 l) excited by a fast electron beam are studied at different energies delivered to the gas. It is shown that the laser operates efficiently when the energy deposited is below 30 J/l. Above specific excitation energies of 60–70 J/l, both the lasing efficiency and the laser output decrease.     

GGG晶体板状激光器特性的研究

测试GGG晶体板条的激光性能,并在高功率泵浦下对板条的热聚焦效应进行了研究.     

New laser dyes

A list of 73 new laser dyes is given. These dyes were found in screening fluorescent dyes from a dye collection using a powerful nitrogen laser of 1 MW peak power and 2.5 nsec pulse width.