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1.
Random deflection of the white light beam during self-focusing and filamentation of a femtosecond laser pulse in water 总被引:1,自引:0,他引:1
W. Liu O. Kosareva I.S. Golubtsov A. Iwasaki A. Becker V.P. Kandidov S.L. Chin 《Applied physics. B, Lasers and optics》2002,75(4-5):595-599
Ti:sapphire femtosecond laser pulse filamentation in competition with optical breakdown in condensed matter is studied both
experimentally and numerically using water as an example. Strong random deflection and modulation of the supercontinuum under
tight focusing conditions were observed. They manifest the beginning of the filamentation process near the highly disordered
plasma created by optical breakdown at the geometrical focus.
Received: 13 June 2002 / Revised version: 16 August 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +1-418/656-2623, E-mail: wliu@phy.ulaval.ca 相似文献
2.
M. Nisoli G. Sansone S. Stagira C. Vozzi S. De Silvestri O. Svelto 《Applied physics. B, Lasers and optics》2002,75(6-7):601-604
A novel spectral broadening technique, based on hollow-fiber cascading, is reported, which allows the generation of a supercontinuum
extending to a bandwidth exceeding 510 THz with excellent spatial beam quality. High-peak-power, sub-7-fs light pulses tunable
from the visible to the near infrared have been generated by compression of portions of the supercontinuum, employing different
sets of chirped mirrors.
Received: 11 July 2002 / Revised version: 3 September 2002 / Published online: 15 November 2002
RID="*"
ID="*"Corresponding author. Fax: +39-02/2399-6126, E-mail: mauro.nisoli@fisi.polimi.it 相似文献
3.
W. Liu O. Kosareva I.S. Golubtsov A. Iwasaki A. Becker V.P. Kandidov S.L. Chin 《Applied physics. B, Lasers and optics》2003,76(3):215-229
The competition between femtosecond laser pulse induced optical breakdown and femtosecond laser pulse filamentation in condensed
matter is studied both experimentally and numerically using water as an example. The coexistence of filamentation and breakdown
is observed under tight focusing conditions. The development of the filamentation process from the creation of a single filament
to the formation of many filaments at higher pulse energy is characterized systematically. In addition, strong deflection
and modulation of the supercontinuum is observed. They manifest themselves at the beginning of the filamentation process,
near the highly disordered plasma created by optical breakdown at the geometrical focus.
Received: 9 July 2002 / Revised version: 15 November 2002 / Published online: 19 March 2003
RID="*"
ID="*"Corresponding author. Fax: +1-418/6562-623, E-mail: wliu@phy.ulaval.ca 相似文献
4.
The wavelength-dependent thermal refractive index gives an extra degree of freedom for adjustment of higher-order dispersion
of a prismatic pulse compressor. The effect allows of fine tuning of both intracavity and extracavity dispersion of ultra-fast
oscillators. The calculations have been carried out using a new and rather handy formalism, which describes the operation
of a prism pulse compressor as a linear function of the ratio of the total glass path in the prisms and the prism apex distance.
The validity of theoretical calculations is supported by experimental evidence.
Received: 16 April 2002 / Published online: 15 November 2002
RID="*"
ID="*"Corresponding author. Fax: +36-62/544658, E-mail: osvay@physx.u-szeged.hu 相似文献
5.
S. Tzortzakis G. Méchain G. Patalano M. Franco B. Prade A. Mysyrowicz 《Applied physics. B, Lasers and optics》2003,76(5):609-612
We report the first observation of the attachment of two single plasma filaments created collinearly in the atmosphere by
IR femtosecond laser pulses. The linked filamentary structure is electrically conductive and emits sub-THz radiation over
its entire length. Concatenation is achieved only for a specific time ordering between the two initial laser pulses. The pulse
producing the filament closer to the laser source must be retarded with respect to the other pulse. This special time ordering
is attributed to the acceleration of light in a self-guided pulse.
Received: 4 March 2003 / Published online: 14 May 2003
RID="*"
ID="*"Corresponding author. Fax: +33-1/6931-9996, E-mail: stzortz@ensta.fr 相似文献
6.
B. Pura J. Petykiewicz M. Wierzbicki R. Cio lek Z. Wrzesiński 《Applied physics. B, Lasers and optics》2002,75(4-5):549-551
By ellipsometric measurements we have observed the polarization variations of the primary light beam, with wavelength λ1=5145 ?, interacting with the secondary light beam of controlled variable polarization, transmitted through a TGS crystal
layer. We present a theoretical explanation based on the second-order optical nonlinearity of TGS.
Received: 4 December 2001 / Revised version: 28 May 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +48-22/660-5447, E-mail: petyk@if.pw.edu.pl 相似文献
7.
100-W average-power, high-energy nanosecond fiber amplifier 总被引:5,自引:0,他引:5
J. Limpert S. Höfer A. Liem H. Zellmer A. Tünnermann S. Knoke H. Voelckel 《Applied physics. B, Lasers and optics》2002,75(4-5):477-479
We report on the fiber-based amplification of a Q-switched Nd:YAG thin-disk laser. At repetition rates between 3 and 50 kHz
output powers up to 100 W are generated. Pulse energies up to 4 mJ, with diffraction-limited beam quality, are generated in
a 30-μm Yb-doped large-mode-area fiber, furthermore pulse energies up to 8 mJ are achieved from a multimode fiber amplifier.
Received: 8 May 2002 / Revised version: 10 July 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +49-3641/65-7680, E-mail: Jens.Limpert@uni-jena.de 相似文献
8.
J. Liao X.J. Zhang F. Xu X.Z. Fan H.T. Wang N.B. Ming 《Applied physics. B, Lasers and optics》2002,75(8):865-869
Optical bistable behavior in a quasi-waveguide containing non-linear film has been experimentally investigated in several
publications in the past years; however, the physical mechanism for optical bistability has not been theoretically explained.
In the present letter, we propose a theoretical model and successfully explain the observed optical bistability of both the
reflected light and the scattered light (m-lines) in a non-linear quasi-waveguide. The optical bistability in the non-linear quasi-waveguide is due to the scattering-type
wavevector mismatch mechanism.
Received: 10 July 2002 / Revised version: 10 September 2002 / Published online: 20 December 2002
RID="*"
ID="*"Corresponding author. Fax: +86-25/359-5535, E-mail: htwang@nju.edu.cn 相似文献
9.
A.B. Fedotov P. Zhou A.N. Naumov V.V. Temnov V.I. Beloglazov N.B. Skibina L.A. Mel’nikov A.V. Shcherbakov A.P. Tarasevitch D. von der Linde A.M. Zheltikov 《Applied physics. B, Lasers and optics》2002,75(6-7):621-627
Photonic-molecule modes of a cobweb-microstructure fiber allow efficient nonlinear optical spectral broadening of nanojoule
femtosecond light pulses. Spectral widths of approximately 200 nm are achieved at the output of a 6-cm sample of such a fiber
for 40-fs Ti:sapphire laser pulses with an energy of a few nanojoules coupled into photonic-molecule modes. Higher values
of the group index and a lower group-velocity dispersion, attainable with higher-order photonic-molecule modes, allow the
efficiency of spectral broadening of femtosecond laser pulses to be increased relative to the efficiency of spectral broadening
in the fundamental photonic-molecule mode.
Received: 9 June 2002 / Revised version: 29 June 2002 / Published online: 22 November 2002
RID="*"
ID="*"Corresponding author. Fax: +7-095/939-3959, E-mail: zheltikov@top.phys.msu.su 相似文献
10.
A high-repetition-rate eye-safe optical parametric oscillator (OPO), using a non-critically phase-matched KTP crystal intracavity
pumped by an acousto-optically (AO) Q-switchedNd:YVO4 laser, is experimentally demonstrated. It is found that the average OPO signal power at 1573 nm can be efficiently increased
by increasing the pulse repetition rate. Moreover, the intracavity OPO process effectively shortens the pulse width so that
it is in the range 5∼8 ns for pulse repetition rates of 10 to 80 kHz. As a result of the relatively short pulse, the peak
power at 1573 nm is higher than 2 kW at a pulse repetition rate of 80 kHz.
Received: 10 July 2002 / Published online: 26 February 2003
RID="*"
ID="*"Corresponding author. Fax: +886-35/729-134, E-mail: yfchen@cc.nctu.edu.tw 相似文献
11.
A. Major N. Langford T. Graf A.I. Ferguson 《Applied physics. B, Lasers and optics》2002,75(4-5):467-469
Self-starting additive-pulse mode locking of a diode-pumped Nd:KGd(WO4)2 laser is demonstrated for the first time. An output power of 0.85 W is achieved with 2.3-ps pulses at a repetition frequency
of 76.5 MHz. The shortest pulse generated had a duration of 1.9 ps.
Received: 2 May 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +44-141/5482891, E-mail: a.major@phys.strath.ac.uk 相似文献
12.
We demonstrate, for the first time to our knowledge, operation of a self-adaptive holographic laser with wavelength selection,
which uses Nd:YLF as the gain medium. The holographic laser was self-starting and, by virtue of the temporal dynamics in writing
the gain grating, passively Q-switched the cavity to produce pulses with 20–50 ns duration. A pulse energy of 184 mJ was obtained
from the system with beams having a TEM00 spatial profile. Single-longitudinal-mode operation was observed with near-transform-limited bandwidth.
Received: 30 July 2002 / Revised version: 1 October 2002 / Published online: 26 February 2003
RID="*"
ID="*"Corresponding author. Fax: +44-20/7594-7744, E-mail: s.y.lam@ic.ac.uk 相似文献
13.
C. Dölle C. Reinhardt P. Simon B. Wellegehausen 《Applied physics. B, Lasers and optics》2002,75(6-7):629-634
. Investigations of the efficient generation of powerful coherent radiation at 82.8 nm by frequency tripling of short-pulse
KrF laser radiation are presented. Argon gas is selected as nonlinear medium due to the resonantly enhanced 3rd-order susceptibility
χ(3)(-3ω,ω,ω,ω). Pulse energies of 100 μJ at 82.8 nm have been measured for a pump pulse energy of 14 mJ. An upscaling to more
than 500 μJ is expected with available more powerful pump lasers. Features of this XUV source and possible applications are
discussed.
Received: 26 July 2002 / Published online: 15 November 2002
RID="*"
ID="*"Corresponding author. Fax: +49-511/7622211, E-mail: reinhardt@iqo.uni-hannover.de 相似文献
14.
T.J. Kulp S.E. Bisson R.P. Bambha T.A. Reichardt U.-B. Goers K.W. Aniolek D.A.V. Kliner B.A. Richman K.M. Armstrong R. Sommers R. Schmitt P.E. Powers O. Levi T. Pinguet M. Fejer J.P. Koplow L. Goldberg T.G. McRae 《Applied physics. B, Lasers and optics》2002,75(2-3):317-327
Quasi-phase-matched (QPM) materials allow the generation of spectroscopically useful infrared radiation in an efficient and
broadly tunable format. Here, we describe several applications of QPM-based light sources to remote and local chemical sensing.
The remote systems are gas imagers that employ a fiber-pumped continuous-wave optical parametric oscillator or a microlaser-pumped,
diode-seeded optical parametric amplifier as the illumination source. Technology described for local sensing includes a cavity
ring down spectrometer that employs a novel optical parametric generator–amplifier to achieve ≥350 cm-1 of contiguous tuning and a long-wave infrared light source based on QPM GaAs. In each case the use of QPM materials in conjunction
with effective pump sources instills simplicity and ruggedness into the sensing systems.
Received: 15 April 2002 / Revised version: 6 June 2002 / Published online: 12 September 2002
RID="*"
ID="*"Corresponding author. Fax: +1-925/294-2595, E-mail: tjkulp@sandia.gov
RID="**"
ID="**"Present address: Corning Inc., Corning, NY 14831, USA
RID="*"
ID="*"Present address: Corning Inc., Corning, NY 14831, USA
RID="**"
ID="**"Present address: Blue Leaf Networks, Sunnyvale, CA 94086, USA
RID="***"
ID="***"Present address: Sandia National Laboratories, Albuquerque, NM 87185, USA 相似文献
15.
T. Brixner 《Applied physics. B, Lasers and optics》2003,76(5):531-540
The usage of Poincaré phase space for the representation of polarization-shaped femtosecond laser pulses is discussed. In
these types of light fields the polarization state (i.e. ellipticity and orientation) changes as a function of time within
a single laser pulse. Such deliberate variation can be achieved by frequency-domain femtosecond pulse shaping in which two
polarization components are manipulated individually. Here it is shown how these light pulses can be represented as temporal
trajectories through the ellipticity-orientation (Poincaré) phase space, whereas conventional light (either continuous-wave
or pulsed) is determined by only one specific Poincaré location. General properties of parametric Poincaré trajectories are
discussed, and their relation to experimentally accessible pulse-manipulation parameters (i.e. amplitudes and phases) determined.
Specifically, it is shown how the maximum rate by which a given polarization state can be turned into a different one (at
significant intensity levels) is limited by the spectral laser bandwidth. Apart from their direct usage in polarization-shaped
pulse representation, Poincaré trajectories also form the basis for intuitive quasi-three-dimensional renderings of the electric
field profile. There, the temporal evolution of polarization, intensity, and chirp is directly apparent in a single illustration.
Received: 10 December 2002 / Published online: 24 April 2003
RID="*"
ID="*"Corresponding author. Fax: +49-931/888-4906, E-mail: brixner@physik.uni-wuerzburg.de 相似文献
16.
We have developed a tunable intense narrow-band 285 nm light source based on frequency doubling of 570 nm light in BBO. At
input powers of 840 mW (including 130 mW used for locking purposes) we generate 99 mW UV radiation with an intensity profile
suitable for laser-cooling experiments. The light is used for laser cooling of neutral magnesium atoms in a magneto-optical
trap (MOT). We capture about 5×106 atoms directly from a thermal beam and find that the major loss mechanism of the magnesium MOT is a near-resonant two-photon
ionization process.
Received: 15 February 2002 / Revised version: 13 August 2002 / Published online: 11 December 2002
RID="*"
ID="*"Corresponding author. Fax: +45-4588/7762, E-mail: dnm@mic.dtu.dk Present address: Mikroelektronik Centret, Technical
University of Denmark, Orsteds Plads, Bldg. 345 East, 2800 Kgs. Lyngby, Denmark 相似文献
17.
Pulse compression of nanojoule pulses in the visible using microstructure optical fiber and dispersion compensation 总被引:2,自引:0,他引:2
S. Lakó J. Seres P. Apai J. Balázs R.S. Windeler R. Szipőcs 《Applied physics. B, Lasers and optics》2003,76(3):267-275
Experimental results on the pulse compression of 1-nJ, 150-fs pulses from a tunable, 76-MHz Ti:sapphire laser oscillator operating
at around 750 nm are reported. The length of the pulses can be compressed to nearly one tenth by applying a high-delta, single-mode
microstructured optical fiber exhibiting zero group-delay dispersion at 767 nm, and by a prism-pair/chirped-mirror compressor.
The experimental results are verified by theoretical investigations modeling the pulse propagation taking into account non-linear
self-phase modulation and fiber dispersion.
Received: 10 June 2002 / Revised version: 15 November 2002 / Published online: 12 February 2003
RID="*"
ID="*"Corresponding author. Fax: +36-1/375-4553, E-mail: szipoecs@sunserv.kfki.hu 相似文献
18.
Soliton-like pulse-shaping mechanism in passively mode-locked surface-emitting semiconductor lasers 总被引:1,自引:0,他引:1
R. Paschotta R. Häring A. Garnache S. Hoogland A.C. Tropper U. Keller 《Applied physics. B, Lasers and optics》2002,75(4-5):445-451
We discuss a mechanism that allows the formation of nearly transform-limited soliton-like pulses in passively mode-locked
optically pumped external-cavity surface-emitting semiconductor lasers. It involves the interplay of positive dispersion and
the nonlinear index changes in gain medium and saturable absorber, while ordinary solitons are based on dispersion and the
Kerr effect. The obtained quasi-soliton pulses share some of the properties of ordinary solitons (in particular, their stability
and near bandwidth-limited nature), while other properties are different. In particular, the pulse duration scales with the
square root of the cavity dispersion, and an excessive drift of the laser wavelength must be avoided by proper design.
Received: 23 April 2002 / Published online: 25 September 2002
RID="*"
ID="*"Corresponding author. Fax: +41-1/633-1059, E-mail: Paschotta@iqe.phys.ethz.ch 相似文献
19.
The generation of programmable complex femtosecond pulses in the mid infrared (3–10 μm) with high precision is reported. Designed
pulse shapes in the near infrared (1–1.6 μm) are transferred to the mid infrared via difference-frequency mixing with a second
infrared pulse spectrally narrowed in a zero-dispersion compressor. In particular, pulse sequences with variable relative
phases have been obtained. The control of the pulse properties is achieved purely electronically, allowing for implementation
into a feedback loop.
Received: 12 December 2003 / Published online: 3 April 2003
RID="*"
ID="*"Corresponding author. Fax: +49-89/32905-200, E-mail: mcm@mpq.mpg.de 相似文献
20.
We present a double-pass non-collinear optical parametric amplifier (NOPA) that delivers 4-fs visible–near-infrared pulses.
The paper discusses geometrical and temporal properties of the NOPA configuration, which allow us to broaden the gain band
of simultaneous parametric amplification in excess of 250 THz. The key elements of the bandwidth enhancement include (i) the
use of a broadband second-harmonic pump, (ii) optimization of the incidence angle of all monochromatic spectral components
of the pump in order to produce a favorable offset of the corresponding phase-matching curves, and (iii) selection of the
chirp rate and time delay between the stretched pump and seed pulses. We next devise a two-stage compressor that incorporates
a flexible mirror for adaptive pulse shaping and develop a simple and trustworthy feedback loop based on a one-dimensional
spectral measurement. Our rapid numerical algorithm for adaptive control of the flexible membrane is found superior to more
complex search routines that are less resistant to the fluctuations of the laser intensity. The automated optimization procedure
results in the generation of two-cycle pulses with a carrier wavelength at ∼600 nm. The absence of deep modulation on the
parametrically amplified spectrum in combination with the adaptive phase correction lead to a high quality of the temporal
profile and allow concentrating 90% of the pulse energy within only a 7.5-fs time window.
Received: 8 April 2002 / Revised version: 26 June 2002 / Published online: 25 September 2002
RID="*"
ID="*"Present address: Institut für Photonik, Technische Universit?t Wien, Gusshausstrasse 27, 1040 Vienna, Austria
RID="**"
ID="**"Corresponding author. Fax: +81-3/5841-4165, E-mail: kobayashi@phys.s.u-tokyo.ac.jp 相似文献