共查询到20条相似文献,搜索用时 31 毫秒
1.
V. M. Orlovsky V. S. Skakun V. F. Tarasenko A. V. Fedenev 《Russian Physics Journal》2000,43(5):372-382
This paper presents the results of investigations of lasing by electronic transitions of xenon, krypton, and neon atoms, cadmium
and zinc ions, and nitrogen molecules and by oscillatory transitions of HF molecules. The processes responsible for the efficiency
of each of the lasers have been studied. The maximum radiation energies achieved are as follows: up to 200 J at λ∼2.8 μm for
a mixture of H2−SF6, up to 100 J at λ-1.73 μm and up to 50 J at λ=2.03 μm for xenon, up to 3 J at λ=358 nm for a mixture of Ar−N2, and up to 0.5 J at λ=585.5 nm for neon.
Institute of High-Current Electronics, Siberian Division of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh
Uchebnykh Zavedenii, Fizika, No. 5, pp. 34–44, April, 2000. 相似文献
2.
N. N. Il’ichev P. V. Shapkin E. S. Gulyamova A. V. Kir’yanov A. S. Nasibov 《Laser Physics》2010,20(5):1091-1094
Effective lasing is obtained in the transversely pumped ZnSe single crystals that are doped with Cr2+ ions using diffusion methods. A Q-switched Er3+-doped glass laser with a radiation wavelength of 1.54 μm is used for pumping. The resulting laser energy is 150 μJ at an
absorbed pump energy of 600 μJ, so that the efficiency is 25% and the slope efficiency is 29%. An increase in the gain (up
to the superluminescence level) due to the application of the transverse pumping of the active element with a substantially
non-uniform distribution of the dopant is discussed. 相似文献
3.
V. F. Tarasenko 《Russian Physics Journal》1999,42(8):670-673
This paper presents the designs and radiation characteristics for lasers operating by self-limited transitions of nitrogen
(λ=337.1 nm) and neon (λ=614.3 nm) and pumped by a pulsed longitudinal discharge, and for atmosphericCO
2 lasers (λ=10.6 μm) pumped by a transverse electron-beam-initiated discharge or by a transverse discharge with uv preionization.
These lasers were put into operation at IHCE in 1969 (the nitrogen and neon lasers), in 1971 (theCO
2 laser pumped by an electron-beam-initiated discharge), and in 1972 (theCO
2 laser pumped by a transverse discharge with uv preionization).
Institute of High Current Electronics, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh
Uchebnykh Zavedenii, Fizika, No. 8, pp. 14–17, August, 1999. 相似文献
4.
2 laser using a miniature water spray is demonstrated. An ablation threshold of 1.4 J/cm2, an optimal energy density of 9–10 J/cm2, and a corresponding specific ablation energy of 25–30 J/mm3 are found for pig thighbone compacta at λ=9.57 μm and a beam waist diameter of 0.5 mm. The water spray alleviates tissue
carbonization even at high laser pulse repetition rates and increases ablation efficiency.
Received: 9 March 1998/Revised version: 6 July 1998 相似文献
5.
J. S. Yu S. Slivken A. Evans M. Razeghi 《Applied Physics A: Materials Science & Processing》2008,93(2):405-408
High-temperature, high-power, and continuous-wave (CW) operation of quantum-cascade lasers with 35 active/injector stages
at λ∼8.85 μm above room temperature is achieved without using a buried heterostructure. At this long wavelength, the use of a
wider ridge waveguide in an epilayer-down bonding scheme leads to a superior performance of the laser. For a high-reflectivity-coated
21 μm×3 mm laser, the output power of 237 mW and the threshold current density of 1.44 kA/cm2 at 298 K under CW mode are obtained with a maximum wall-plug efficiency of 1.7%. Further improvements were observed by using
a 4-mm-long cavity. The device exhibits 294 mW of output power at 298 K and it operates at a high temperature, even up to
358 K (85°C). The full widths at half-maximum of the laser beam in CW operation for the parallel and the perpendicular far-field
patterns are 25°and 63°, respectively. 相似文献
6.
M. Stanislawki J. Meister T. Mitra M.M. Ivanenko K. Zanger P. Hering 《Applied physics. B, Lasers and optics》2001,72(1):115-120
The Er:YAG and the CO2 laser are competitors in the field of hard tissue ablation. The use of Er:YAG lasers (2.94 μm, pulse length
L of 100 to 200 μs) show smaller areas of thermal defects then ‘‘superpulsed’’ CO2 lasers with pulse lengths of approximately 100 μs. Only the development of a Q-switched CO2 laser (9.6 μm, τL=250 ns) allowed for similar results. In this paper new results for the Er:YAG and the Q-switched CO2 laser under the influence of water spray will be presented. Several parameters are of special interest for these investigations:
the specific ablation energy, which shows a minimum for the CO2 laser at an energy density of 9 J/cm 2 and a broad shallow minimum in the range of 10 to 70 J/cm2 for the Er:YAG laser, and comparison of the cut-shape and depth. Surface effects and cutting velocity are discussed based
on SEM pictures.
Received: 19 July 2000 / Revised version: 1 November 2000 / Published online: 30 November 2000 相似文献
7.
Three powerful wide-aperture CO2 lasers with the wavelength λ = 1.06 μm (a laser pumped by electron-beam-controlled discharge, a high-pressure continuously
tunable laser, and a repetitively pulsed laser) are created and studied. A method for the volume discharge generation proposed
at the High-Current Electronics Institute is used for the development of the lasers.
Original Text ? Astro, Ltd., 2006. 相似文献
8.
W. Holzer A. Penzkofer T. Pertsch N. Danz A. Bräuer E.B. Kley H. Tillmann C. Bader H.-H. Hörhold 《Applied physics. B, Lasers and optics》2002,74(4-5):333-342
Wave-guided thin-film distributed-feedback (DFB) polymer lasers are fabricated by spin coating a PPV-derived semiconducting
polymer, thianthrene-DOO-PPV, onto oxidised silicon wafers with corrugated second-order periodic gratings. The gratings are
written by reactive ion beam etching. Laser action is achieved by transverse pumping with picosecond laser pulses (wavelength
347.15 nm, duration 35 ps). The DFB-laser surface emission and edge emission are analysed. Outside the grating region the
polymer film is used for comparative wave-guided travelling wave laser (amplified spontaneous emission (ASE)) studies. The
pump pulse threshold energy density for wave-guided DFB-laser action (4–9 μJ cm-2) is found to be approximately a factor of two lower than the threshold for wave-guided travelling wave laser action. The
spectral width of the DFB laser (down to ΔλDFB≈0.07 nm) is considerably narrower than that of the travelling wave laser (ΔλTWL≈14 nm). The DFB-laser emission is highly linearly polarised transverse to the grating axis (TE mode). Only at high pump pulse
energy densities does an additional weak TM mode build up. The surface-emitted DFB-laser radiation has a low divergence along
the grating direction. For both the DFB lasers and the travelling wave lasers, gain saturation occurs at high excitation energy
densities.
Received: 7 January 2002 / Revised version: 15 February 2002 / Published online: 14 March 2002 相似文献
9.
B. M. Kovalchuk V. F. Losev G. A. Mesyats V. F. Tarasenko 《Russian Physics Journal》2000,43(5):352-357
High-efficiency, high-power pulsedXeCl
* andKrF
* lasers pumped with an electron beam and laser systems based on these lasers have been developed. This paper describes the
principles embodied in their development and design. The results of investigations on the formation of high-quality, high-power
pulses are presented. Pulses with a radiation energy of up to 2000 and 100 J have been obtained at λ=308 and 249 nm, respectively,
with a minimum 10 μrad divergence of the beam.
Institute of High-Current Electronics, Siberian Division of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh
Uchebnykh Zavedenii, Fizika, No. 5, pp. 12–18, April, 2000. 相似文献
10.
J.C. Diettrich I.T. McKinnie D.M. Warrington 《Applied physics. B, Lasers and optics》1999,69(3):203-206
We have developed a gain-switched room-temperature Cr:forsterite laser operating at repetition rates of between 1 and 34 kHz,
and pumped by a continuous wave, Q-switched Nd:YAG laser. With optimised output coupling, an output pulse energy of 52 μJ
was measured at 1.5 kHz repetition rate, corresponding to 11% efficiency and 13% slope efficiency. Threshold pulse energy
was 53 μJ. Output power of 370 mW was obtained at 10 kHz repetition rate and 4.4 W pump power. Water cooling was not required
for repetition rates up to 10 kHz. In a tunable, folded resonator, the Cr:forsterite wavelength tuned between 1173 and 1338 nm.
This laser operated with maximum pulse energy of 34 μJ, efficiency of 13%, and power of 307 mW. The laser output was close
to diffraction-limited with M2 of 1.2.
Received: 6 January 1999 / Published online: 29 July 1999 相似文献
11.
M. S. Gaponenko I. A. Denisov V. E. Kisel A. M. Malyarevich A. A. Zhilin A. A. Onushchenko N. V. Kuleshov K. V. Yumashev 《Applied physics. B, Lasers and optics》2008,93(4):787-791
Glass doped with PbS quantum dots is presented as a saturable absorber (SA) for a passive Q-switching of a diode-pumped 1.9 μm Tm:KYW laser. Output pulses with energy of 44 μJ at a repetition rate of 2.5 kHz with
an average output power of 110 mW were obtained. The Q-switching conversion efficiency was 33%. The absorption saturation intensity of the glass doped with PbS quantum dots with
a mean radius of 5.2 nm at a wavelength of 2 μm was measured to be 1.5 MW/cm2. 相似文献
12.
H. Daido S. Yamagami M. Suzuki H. Azuma I.W. Choi H. Fiedorowicz 《Applied physics. B, Lasers and optics》2001,72(3):385-387
We have measured low-energy ion emission from a gas-puff laser-plasma X-ray source. The ions may cause the degradation of
the condenser mirror of the extreme ultra-violet projection lithography system. A 0.7 J in 8 ns Nd:YAG laser at 1.06 μm was
focused onto the xenon gas-puff target with an intensity of ∼1012 W/cm2. The silicon (111) plates, placed at a distance of 32 mm from the laser-interaction region, were exposed with the xenon ions.
The average ion energy was measured to be less than 50 eV with a Faraday-cup detector placed close to the silicon plates.
The xenon deposition occurred in the silicon plates with a depth of less than 40 nm. The deposition density was measured with
a quadrupole secondary ion mass spectrometer to be 1021 /cm3 after 1500 laser shots. The energy-conversion efficiency from the laser energy into the ions is ∼0.1%/4 π sr/shot. For the
lithography system, if we can remove such ion bombardment completely using novel techniques such as electro-magnetic devices
or gas flow curtain techniques, the lifetime of the condenser mirror will be extended significantly.
Received: 20 November 2000 / Published online: 9 February 2001 相似文献
13.
M. P. Frolov Yu. V. Korostelin V. I. Kozlovsky V. V. Mislavsky Yu. P. Podmar’kov Ya. K. Skasyrsky A. A. Voronov 《Journal of Russian Laser Research》2011,32(6):528-536
We realized laser generation on a Fe2+:ZnTe crystal for first time. The crystal was pumped at room temperature by 40 ns pulses of an Er:YAG laser operating at a
wavelength of 2.94 μm in the Q-switching mode. The output energy of the Fe2+:ZnTe laser was 0.18 mJ at a slope efficiency of 2.4% with respect to absorbed pumping energy. We achieved tuning of the Fe2+:ZnTe laser generation wavelength within the range of 4.35–5.45 μm using a prism-dispersion cavity. 相似文献
14.
A. A. Hakhoumian E. M. Laziev A. S. Nikoghosyan D. L. Hovhannisyan G. D. Hovhannisyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2010,45(1):17-24
We study the influence of spatial boundedness of a femtosecond laser pulse (FLP) on the efficiency of generation of difference
frequency radiation (DFR) in a GaAs crystal with a periodic domain structure. It is shown that at propagation of DFR a spectral-angular
filtration occurs in the transverse distribution of the beam. An expression is obtained for the frequency-angular spectrum
of DFR. For a pump pulse with the duration of 100 fs, the beam radius of 24μm, the energy of 30 nJ, and the wavelength of
1.98μm propagating in 1.716-mm long GaAs crystal with the domain structure period of 74.6μm the efficiency of generation of
DFR at the wavelength of 14μm is calculated to be close to 2×10−6. 相似文献
15.
We describe a mopa structured all-fiber 15 μm fiber amplifier cascade. A single-mode diode laser generating 1064 nm wavelength,
several nanosecond pulses at 100 Hz repetition was adopted to seed a corepumping amplifier featuring a 6 μm core Yb-doped
fiber. Multi-stage pulse-pumping technology was applied to eliminate ASE as much as possible and ease the heat load of the
system that leads to the freedom of temperature control of the laser diode. The master oscillator-power amplifier (MOPA) generated
1064 nm, 18 ns pulse-width, 100 Hz repetition of 220 μJ single pulse energy, peak power >12 kW with single transverse output.
The pulse energy of 220 μJ is the largest to date in the all-fiber MOPA amplifier with core diameter around 15 μm to our knowledge. 相似文献
16.
V. P. Chebotayev V. M. Klementyev Yu. A. Matyugin 《Applied Physics A: Materials Science & Processing》1976,11(2):163-165
The present paper offers a scheme of synthesis and measurement of frequency of 0.63 μm laser radiation based on mixing of
three frequencies of a cascade He-Ne laser generating simultaneously the three lines: 3.39, 2.39, and 1.15 μm. Reported is
an experimental observation of coherent radiation with a wavelength of 0.63 μm arising in mixing of the three frequencies
in a gas. The effective frequency transformation was performed at the nonlinear interaction of three fields resonant with
coupled transitions in neon. Due to the resonance conditions an efficiency of the frequency transformation in a gas proved
to be 8–10 orders higher than that in nonlinear optical crystals. 相似文献
17.
Pogorelsky I. V. Polyanskiy M. N. Babzien M. Yakimenko V. Dover N. P. Palmer C. A. J. Najmudin Z. Schreiber J. Shkolnikov P. Dudnikova G. 《Laser Physics》2011,21(7):1288-1294
A picosecond CO2 laser was used successfully in a number of experiments exploring advanced methods of particle acceleration [1]. Proton acceleration
from gas-jet plasma exemplifies another advantage of employing the increase in laser wavelength from the optical to the mid-IR
region. Recent theoretical- and experimental-studies of ion acceleration from laser-generated plasma point to better ways
to control the ion beam’s energy when plasma approaches the critical density. Studying this regime with solid-state lasers
is problematic due to the dearth of plasma sources at the critical electron density ∼1021 cm−3, corresponding to laser wavelength λ = 1 μm. CO2 laser offers a solution. The CO2 laser’s 10 μm wavelength shifts the critical plasma density to 1019 cm−3, a value attainable with gas jets. Capitalizing on this approach, we focused a circular polarized 1-TW CO2 laser beam onto a hydrogen gas jet and observed a monoenergetic proton beam in the 1–2 MeV range. Simultaneously, we optically
probed the laser/plasma interaction region with visible light, revealing holes bored by radiation pressure, as well as quasi-stationary
soliton-like plasma formations. Our findings from 2D PIC simulations agree with experimental results and aid in their interpretation. 相似文献
18.
B. M. Walsh 《Laser Physics》2010,20(3):622-634
Dual wavelength lasers are discussed, covering fundamental aspects on the spectroscopy and laser dynamics of these systems.
Results on Tm:Ho:Er:YAG dual wavelength laser action (Ho at 2.1 μm and Er at 2.9 μm) as well as Nd:YAG (1.06 and 1.3 μm) are
presented as examples of such dual wavelength systems. Dual wavelength lasers are not common, but there are criteria that
govern their behavior. Based on experimental studies demonstrating simultaneous dual wavelength lasing, some general conclusions
regarding the successful operation of multi-wavelength lasers can be made. 相似文献
19.
B. P. Aduev G. M. Belokurov D. R. Nurmukhametov 《Russian Journal of Physical Chemistry B, Focus on Physics》2012,6(4):511-516
The effect of temperature on the threshold of explosive decomposition of pentaerythritol tetranitrate samples with a density of ρ = 1.73 g/cm3 containing 0.1 wt % 100- to 120-nm aluminum particles under the action of laser pulses (λ = 1.06 μm, τ = 20 ns) is examined. A model capable of describing the experimental results is proposed, according to which the explosive decomposition of the samples is associated with the absorption of laser radiation by structural defects of pentaerythritol tetranitrate and aluminum nanoparticles. It is demonstrated that, at 300 K, explosion initiation is largely determined by the heating of aluminum nanoparticles with the formation of chemical decomposition kernels nearby. 相似文献
20.
S. Borodziuk A. Kasperczuk T. Pisarczyk S. Yu. Gus'kov J. Ullschmied E. Krousky K. Masek M. Pfeifer K. Rohlena J. Skala M. Kalal J. Limpouch P. Pisarczyk 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(2):311-317
Efficiency studies of laser driven thin metal disks
acceleration using the first harmonic (λ1=1.315 μm) of
the Prague Asterix Laser System (PALS) and subsequent craters creation
produced by collisions of these disks with massive targets are presented.
Several different disks made of aluminium and copper foils with diameters of
300 μm and 600 μm and thicknesses of 11 μm (Al) and 3.6 μ
m (Cu) were employed. Disks were placed at the distance of either 100 μ
m or 300 μm in front of aluminium massive targets. The following
irradiation conditions were used: the laser beam energy of 120 J, the focal
spot diameter of 200 μm, and the pulse duration of 0.4 ns (FWHM). A
three-frame interferometric system was employed to determine electron
density distributions in plasma corona. Shape and volume of craters were
obtained by crater replica technology and microscopy measurements. The aim
of these investigations was to analyse conditions leading to the most
effective energy transfer in the process of collision of the accelerated
disks with solid targets. The overall efficiency of these processes was
characterized by the volume of craters produced in such targets. 相似文献