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1.
M. Schneider A. Hinz A. Groh K. M. Evenson W. Urban 《Applied physics. B, Lasers and optics》1987,44(4):241-245
Frequency stabilization of the CO laser using a CO lamb-dip is achieved in the range from 5.0–6.3 m. The CO saturation signal is obtained from a low-pressure discharge in absorption and is detected using optogalvanic, detection. The frequency stability and reproducibility has been verified to be better than 100 kHz; this is an improvement of more than one order of magnitude compared with locking techniques using CO laser gain profiles.Alexander von Humboldt Awardee from National Bureau of Standards, Boulder, Colorado, USA 相似文献
2.
P. J. M. Peters M. Trentelman Q. C. Mei W. J. Witteman 《Applied physics. B, Lasers and optics》1994,59(5):533-535
The discharge characteristics of the XeF* (BX) laser are investigated. The NF3 and Xe partial pressure of the laser gas mixture and the total gas pressure have been varied. A highest specific output energy of 4.7 J/l with an efficiency of 0.5% was obtained from a X-ray preionized Ne/Xe/NF3 gas mixture at 6 bar with single-pulse excitation through a multichannel spark gap. 相似文献
3.
J. Nilsen J. C. Moreno B. J. MacGowan J. A. Koch 《Applied physics. B, Lasers and optics》1993,57(5):309-311
We report lasing for the first time in nickel on the neon-like J=01, 3p3s transition at 231 Å as well as several weaker transitions including the J=2»1 lines at 298 Å and 304 Å. Amplification is seen only when the prepulse technique of using a low intensity prepulse before the main optical drive pulse is used to illuminate the nickel target. The prepulse technique is also shown to produce lasing in copper and dramatically improve the output of the germanium laser. 相似文献
4.
5.
Development of a tunable mid-IR difference frequency laser source for highly sensitive airborne trace gas detection 总被引:4,自引:0,他引:4
Richter D Fried A Wert BP Walega JG Tittel FK 《Applied physics. B, Lasers and optics》2002,75(2-3):281-288
The development of a compact tunable mid-IR laser system at 3.5 μm for quantitative airborne spectroscopic trace gas absorption
measurements is reported. The mid-IR laser system is based on difference frequency generation (DFG) in periodically poled
LiNbO3 and utilizes optical fiber amplified near-IR diode and fiber lasers as pump sources operating at 1083 nm and 1562 nm, respectively.
This paper describes the optical sensor architecture, performance characteristics of individual pump lasers and DFG, as well
as its application to wavelength modulation spectroscopy employing an astigmatic Herriott multi-pass gas absorption cell.
This compact system permits detection of formaldehyde with a minimal detectable concentration (1σ replicate precision) of
74 parts-per-trillion by volume (pptv) for 1 min of averaging time and was achieved using calibrated gas standards, zero air
background and rapid dual-beam subtraction. This corresponds to a pathlength-normalized replicate fractional absorption sensitivity
of 2.5×10-10 cm-1.
Received: 29 April 2002 / Published online: 21 August 2002
RID="*"
ID="*"Corresponding author. Fax: +1-303/497-1492, E-mail: dr@ucar.edu 相似文献
6.
D. Sabourdy V. Kermène A. Desfarges-Berthelemot M. Vampouille A. Barthélémy 《Applied physics. B, Lasers and optics》2002,75(4-5):503-507
The coherent combining of two Nd:YAG lasers using a Vernier–Michelson-type cavity has been demonstrated. The spectral behaviour
and the energetic performance are reported. We firstly show that the combining efficiency is not strongly spoilt by the gain
imbalance between the two amplifying media, and secondly, that despite the interferometric nature of the cavity, the Vernier–Michelson
laser can withstand environmental perturbations without alteration in output power.
Received: 25 April 2002 / Revised version: 18 May 2002 / Published online: 25 September 2002
RID="*"
ID="*"Corresponding author. Fax: +33-5/5545-7253, E-mail: kermene@ircom.unilim.fr 相似文献
7.
T.V. Andersen J. Thogersen S.R. Keiding J.J. Larsen 《Applied physics. B, Lasers and optics》2003,76(6):639-644
We demonstrate intracavity frequency doubling of a standard femtosecond Ti:sapphire oscillator. The cavity is extended with
a pair of focusing mirrors and a 0.5-mm-thick BBO crystal. We achieve a repetition rate of 50 MHz and simultaneously generate
22 mW of 55-fs pulses at 810 nm and 200 mW of 73-fs pulses at 405 nm, which corresponds to 4 nJ per pulse. We create a total
of 330-mW, 405-nm light when pumping the Ti:sapphire crystal with 5.7 W from an Ar-ion laser, corresponding to a conversion
efficiency of 5.7%. No saturation is found, which implies that higher outputs can be achieved with higher pump rates. Preliminary
results from the use of blue pulses as pump in an optical parametric amplifier seeded by pulses from a photonic crystal fiber
are presented.
Received: 27 January 2003 / Revised version: 27 March 2003 / Published online: 12 May 2003
RID="*"
ID="*"Corresponding author. Fax: +45-861/96199, E-mail: tva@chem.au.dk 相似文献
8.
An All-Solid-State Tunable Dual-Wavelength Ti:Sapphire Laser with Quasi-Continuous-Wave Outputs 下载免费PDF全文
A high power dual-wavelength Ti:sapphire laser system with wide turning range and high efficiency is described, which consists of two prism-dispersed resonators pumped by an a11-solid-state frequency-doubled Nd:YAG laser. Tunable dual-wavelength outputs, with one wavelength range from 750nm to 795nm and the other from 80Ohm to 850nm, have been demonstrated. With a pump power of 23 W at 532nm, a repetition rate of 6.5kHz and a pulse width of 67.6ns, the maximum dual-wavelength output power of 5.6 W at 785.3nm and 812.1 run, with a pulse width of 17.2ns and a line width of 2nm, has been achieved, leading to an optical-to-optical conversion efficiency of 24.4%. 相似文献
9.
The possible construction of a self-contained and compact pulsed chemical HF-laser based on an auto-wave photon-branched chain
reaction initiated in a gaseous disperse medium composed of H2-F2-O2-He and Al particles by focused external IR radiation is theoretically substantiated. It is shown that an autonomous system
and minimization of the parameters of the main pulsed HF-laser units are achievable due to both the effect of ignition of
the laser-chemical reaction in an auto-wave regime under the condition of external beam focusing and the effect of a huge
laser energy gain of 1011. These effects provide strong reduction of the input pulse energy necessary for initiation up to ∼10-8 J, and make it possible to construct a self-contained laser with kilojoule output energy, which can be initiated by a small
submicrojoule master oscillator powered by an accumulator. Due to an increase in the general pressure of working gases up
to P=2.3 bar and optimization of the parameters of the dispersed component (Al particles with radius r0=0.09 μm and concentration N0=1.4×109 cm-3) and the composition of the working mixture, the HF-laser system will ensure an output energy up to ∼1.5 kJ in a pulse from
the rather small volume of ∼2 L of the active medium.
Received: 18 April 2000 / Revised version: 21 August 2000 / Published online: 8 November 2000 相似文献
10.
N. Lee D. Thirumalai 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,12(4):599-605
The effect of electrostatic interactions on the stretching of DNA is investigated using a simple worm like chain model. In
the limit of small force there are large conformational fluctuations which are treated using a self-consistent variational
approach. For small values of the external force f, we find the extension scales as where is the Debye screening length. In the limit of large force the electrostatic effects can be accounted for within the semiflexible
chain model of DNA by assuming that only small excursions from rod-like conformations are possible. In this regime the extension
approaches the contour length as where f is the magnitude of the external force. The theory is used to analyze experiments that have measured the extension of double-stranded
DNA subject to tension at various salt concentrations. The theory reproduces nearly quantitatively the elastic response of
DNA at small and large values of f and for all concentration of the monovalent counterions. The limitations of the theory are also pointed out.
Received 13 October 1998 and Received in final form 9 June 1999 相似文献