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1.
A. Marcinkevičius V. Mizeikis S. Juodkazis S. Matsuo H. Misawa 《Applied Physics A: Materials Science & Processing》2003,76(2):257-260
We studied the peculiarities of femtosecond laser microfabrication in silica glass with a refractive index that did not exactly
match the value for which the focusing optics is designed. Spherical aberrations resulting from a small refractive index mismatch
were found to increase the size and distort the shape of photodamaged regions, thus reducing the spatial resolution of the
microfabrication. However, these undesirable effects can be minimized, providing that the focusing depth inside the glass
is not too large, and the laser intensity is kept close to the light-induced damage threshold.
Received: 3 December 2001 / Accepted: 11 April 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: +81-88/656-7598, E-mail: misawa@eco.tokushima-u.ac.jp 相似文献
2.
G. Zhang H. Wang Y. Yu F. Xiong G. Tang W. Chen 《Applied physics. B, Lasers and optics》2003,76(6):677-681
All-optical switching and beam deflection of 2-(2′-hydroxyphenyl) benzoxazole (HBO) in three species of solvent (cyclohexane, ethanol and dimethyl sulfoxide) have been investigated
by using third-harmonic generation (355 nm) of a mode-locked Nd:YAG laser as a pump beam and a continuous-wave He-Ne laser
(632.8 nm) as a probe beam. The nonlinear refractive indices of HBO in different solvents are determined by using the Z-scan
technique. The optical switching and beam-deflection effects are due to the change of the refractive index of HBO under the
pump beam. Through the study of the absorption spectra and the fluorescence spectra of HBO in different solvents, we conclude
that the principal reason for the change of the refractive index of HBO is not the thermal effect because of absorption of
the pump beam, but the excited-state intramolecular proton-transfer (ESIPT) effect of HBO under the pump beam. As the ESIPT
process is very fast, HBO might be an excellent material for high-speed optical switching.
Received: 28 October 2002 / Revised version: 18 March 2003 / Published online: 2 June 2003
RID="*"
ID="*"Corresponding author. Fax: +86-22/2350-1242, E-mail: zhanggl@nankai.edu.cn 相似文献
3.
Transmission electron microscopy studies of femtosecond laser induced modifications in quartz 总被引:1,自引:0,他引:1
T. Gorelik M. Will S. Nolte A. Tuennermann U. Glatzel 《Applied Physics A: Materials Science & Processing》2003,76(3):309-311
Cross-sectional transmission electron microscopy investigations of femtosecond laser induced sub-micrometer structural modifications
inside crystalline quartz were carried out. Modifications from single laser shots and from lines built of overlapping shots
were imaged. Both single laser shot modifications and line structures show an amorphous core surrounded by a disturbed crystalline
structure. A strong strain field surrounding the central, irradiated, core is responsible for an increase of the refractive
index. Finite element method calculations of the strain field show maxima on both sides of the irradiated core, which are
in good agreement with optical measurements of the refractive-index change.
Received: 29 September 2001 / Accepted: 9 July 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +49-3641/947792, E-mail: tatiana.gorelik@rz.uni-jena.de 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.
Y. Du M.-S. Zhang J. Wu L. Kang S. Yang P. Wu Z. Yin 《Applied Physics A: Materials Science & Processing》2003,76(7):1105-1108
SrTiO3 thin films were prepared on a fused-quartz substrate by pulsed laser deposition (PLD). Dense and homogeneous films with a
thickness of 260 nm were prepared. Optical constants (refractive index n and extinction coefficient k) were determined from
the transmittance spectra using the envelope method. The optical band gap energy of the films was found to be 3.58 eV, higher
than the 3.22 eV for bulk SrTiO3, attributable to the film stress exerted by the substrate. The dispersion relation of the refractive index vs. wavelength
follows the single electronic oscillator model. The refractive index and the packing density for the PLD-prepared SrTiO3 thin films are higher than those for the SrTiO3 films prepared by physical vapor deposition, sol–gel and RF sputtering.
Received: 18 March 2002 / Accepted: 7 October 2002 / Published online: 8 January 2003
RID="*"
ID="*"Corresponding author. Fax: +86-25/359-5535, E-mail: mszhang@nju.edu.cn 相似文献
6.
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
7.
A. I. Frank P. Geltenbort M. Jentschel D. V. Kustov G. V. Kulin A. N. Strepetov 《JETP Letters》2011,93(7):361-365
The results of a new experiment on the observation of the effect of accelerating matter in neutron optics are reported. It has been shown that the velocity of neutrons periodically varies when they pass through a harmonically moving refractive sample. The idea of the experiment is based on time focusing, i.e., on the fact that the periodic modulation of the velocity of neutrons leads to the oscillation of the flux density at the observation point. The magnitude of the effect is in reasonable agreement with the theoretical predictions. The experiment has been carried out with ultracold neutrons and a change of ±1 cm/s has been detected in the neutron velocity. 相似文献
8.
S.-H. Cho H. Kumagai K. Midorikawa 《Applied Physics A: Materials Science & Processing》2003,76(5):755-761
The time-resolved dynamics of plasma self-channeling and refractive index bulk modification in silica glasses were first observed
in situ using a high-intensity femtosecond (110 fs) Ti:sapphire laser (λp=790 nm). Plasma channeling is induced in silica glass at an irradiation higher than an input intensity of 1.5×1012 W/cm2 and photoinduces either the refractive-index modification or optical crack modification. In the domain of refractive-index
modification, the lifetime of induced plasma self-channeling was 20 ps and the structural transition time for forming the
refractive-index change was 10 ps. In the domain of optical cracks, however, the lifetime of induced plasma formation was
30 ps and the structural transition time for forming the optical cracks was 40 ps. According to electron spin resonance spectroscopic
(ESP) measurement, it was found that the defect concentration of the SiE′ center increased significantly in the refractive index modification region. A maximum value of the refractive-index change
Δn was measured to be 1.6×10-2. The intensity profile of the output beam transmitted through the refractive-index modification showed that the bulk modification
produced a permanent optical waveguide.
Received: 8 April 2002 / Accepted: 12 April 2002 / Published online: 22 November 2002
RID="*"
ID="*"Corresponding author. Fax: +81-48/462-4682, E-mail: shcho@riken.go.jp 相似文献
9.
L. Nedelchev L. Nikolova A. Matharu P.S. Ramanujam 《Applied physics. B, Lasers and optics》2002,75(6-7):671-676
A study of the propagation of elliptically polarized light and the resulting formation of macroscopic chiral structures in
a series of azobenzene side-chain copolyesters, in which the morphology is varied from liquid crystalline to amorphous, is
reported. Real-time measurements are presented, showing the dynamic behavior of the photoinduced rotation of the polarization
ellipse in the different samples. The relationship between the ellipticity of the recording light and the linear birefringence
induced is studied. A numerical solution that takes into account the influence of the photoinduced linear dichroism on the
light propagation through the samples is presented.
Received: 10 June 2002 / Revised version: 26 July 2002 / Published online: 15 November 2002
RID="*"
ID="*"Corresponding author. Fax: +45-4677/4588, E-mail: lian.nedelchev@risoe.dk
RID="**"
ID="**"Permanent address: Department of Chemistry and Physics, The Nottingham Trent Unversity, Clifton Lane, Nottingham NG11 8NS,
England 相似文献
10.
S.L. Xu Q.D. Zeng P. Wu Y.H. Qiao C. Wang C.L. Bai 《Applied Physics A: Materials Science & Processing》2003,76(2):209-212
The molecular assembly of three different trialkyloxy-substituted benzaldehydes on graphite has been studied using scanning
tunneling microscopy (STM). It is found that these benzaldehydes, which do not have intermolecular hydrogen bonding, could
form a lamella arrangement in which the headgroups are aligned side by side. The effect due to the alkyl chain length on the
lamella structure is also presented.
Received: 21 January 2002 / Accepted: 22 March 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: +86-10/6255-7908 相似文献
11.
12.
A. I. Frank P. Geltenbort M. Jentschel D. V. Kustov G. V. Kulin V. G. Nosov A. N. Strepetov 《Physics of Atomic Nuclei》2008,71(10):1656-1674
Results of experiments aimed at observing the change in the energy of a neutron traversing an accelerated refractive sample are reported. The experiments were performed with ultracold neutrons, the energy transfer in these experiments being ±(2?6) × 10?10 eV. The results suggest the existence of the effect and agree with theoretical predictions to a precision higher than 10%. A similar effect was previously predicted for the change in the frequency of an electromagnetic wave traversing an accelerated dielectric slab. In all probability, the effect has a very general nature, but it is presently observed only in neutron optics. 相似文献
13.
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
14.
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
15.
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
16.
Radhi M. Chyad Mohd Zubir Mat Jafri Kussay N. Mutter Kamarulazizi Ibrahim 《Optik》2012,123(10):860-862
By using 3-D geometric optics, the effect of a modified cladding on the transmission of light through optical fiber is investigated. Analysis of the light transmission of the optical fiber as function of the modified cladding refraction index and length are presented for various input illumination focused and compared with 3-D ray theory. Applications to chemical sensors are also discussed.The intensity of light signal transmitted through an optical fiber, which its cladding over a finite length is removed, is used as a sensor of refractive of liquids, in which the fiber is immersed. The transmitted light intensity is measured as a function of liquid refractive index for different lengths of the unclad section of the fiber and at each unclad length its sensitivity to change in refractive index of liquid is presented. 相似文献
17.
H. Kreutzmann A. Sanpera L. Santos M. Lewenstein D. Hellweg L. Cacciapuoti M. Kottke T. Schulte K. Sengstock J.J. Arlt W. Ertmer 《Applied physics. B, Lasers and optics》2003,76(2):165-172
Quasi-one-dimensional Bose–Einstein condensates (BECs) in elongated traps exhibit significant phase fluctuations even at very
low temperatures. We present recent experimental results on the dynamic transformation of phase fluctuations into density
modulations during time of flight and show the excellent quantitative agreement with the theoretical prediction. In addition
we confirm that, under our experimental conditions, in the magnetic trap density modulations are strongly suppressed even
when the phase fluctuates. We also discuss our theoretical results on control of the condensate phase by employing a time-dependent
perturbation. Our results set important limitations on future applications of BECs in precision atom interferometry and atom
optics, but at the same time suggest pathways to overcome these limitations.
Received: 17 August 2002 / Published online: 15 January 2003
RID="*"
ID="*"Corresponding author. Fax: +49-511/762-3023, E-mail: Helge.Kreutzmann@ITP.uni-hannover.de 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.
We report the observation of light filaments produced by a picosecond laser pulse in the visible. The pulse trapped in the
filamentary mode experiences large-scale self-phase modulation, with almost 100-fold spectral broadening along with apparent
shortening of the leading edge. Spatial-temporal properties of the light filament reveal rather complex propagation dynamics.
Received: 7 August 2002 / Revised version: 12 September 2002 / Published online: 11 December 2002
RID="*"
ID="*"Corresponding author. Fax: +370-2/3660-06, E-mail: audrius.dubietis@ff.vu.lt 相似文献
20.
Photonic crystals with stop bands located in the visible region have been fabricated by crystallizing monodispersed spherical
colloids (made of polystyrene or silica) into cubic-close-packed lattices within specially designed packing cells. These crystals
were oriented with their (111) planes parallel to their solid supports, and the number of these planes could be conveniently
controlled from 13 to 127 layers by varying the thickness of packing cells. In accordance, the stop-band attenuation of these
crystals monotonically increased from 1 to 21 dB. Our transmission spectral measurements indicated that there exists a non-linear
dependence between the stop-band attenuation and the total number of (111) planes, and this dependence could be quantitatively
simulated using the dynamic light scattering model or the photonic analogy to KKR method. The colloidal crystals presented
here should find use as components in fabricating optical devices that include sensors, mirrors, filters, switches and waveguides.
Received: 17 May 2002 / Accepted: 25 July 2002 / Published online: 4 December 2002
RID="*"
ID="*"Corresponding author. Fax: +1-206/685-8665, E-mail: xia@chem.washington.edu 相似文献