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1.
2.
T. Fessant 《Applied physics. B, Lasers and optics》1998,67(6):769-772
Received: 27 July 1998/Revised version: 25 September 1998 相似文献
3.
E. Schöll K. Ketterer E. H. Böttcher D. Bimberg 《Applied physics. B, Lasers and optics》1988,46(1):69-77
A gain-switched semiconductor laser is shown to act as an optical gate with picosecond resolution and amplification for light pulses from another laser source. The amplification mechanism and the gate width change qualitatively when the gate laser undergoes a transition from a pumping rate slightly below the dynamic laser threshold to slightly above the dynamic threshold. If the gate laser is pumped below but close to its dynamical threshold, unsaturated amplification of an external signal pulse occurs over a delay time range between the external optical pulse and the electrical driving pulse of about 100–200 ps which is equivalent to the optical gate width. The signal amplification is observed to increase by two orders of magnitude and the gate width decreases by one order of magnitude if the gate laser is pumped slightly above the dynamical threshold. Amplification then occurs for input signals injected much earlier. A detailed theory of coherent, time-dependent amplification including the nonlinear dynamics of the semiconductor laser is shown to account for the observations. Both amplification regimes, below and above threshold, are reproduced in the numerical simulations. The extremely short and highly sensitive gate range above threshold is identified as being due to the gain maximum related with the first relaxation oscillation of the laser. 相似文献
4.
Noise as reliability screening for semiconductor lasers 总被引:1,自引:0,他引:1
H. Guijun S. Jiawei G. Yinbing Y. Xiaosong L. Jing 《Applied physics. B, Lasers and optics》2003,76(4):359-363
The low-frequency electrical noise in semiconductor lasers is measured and used for device-reliability screening, which is
a sensitive and non-destructive method. In the experiment, we developed some approaches to improve the validity of reliability
screening by using noise criteria. A new method of determining the threshold level of noise criteria is given. The experimental
results show that this method is effective.
Received: 26 September 2002 / Revised version: 28 January 2003 / Published online: 9 April 2003
RID="*"
ID="*"Corresponding author. Fax: +86-431/462-7013, E-mail: huguijun@sina.com 相似文献
5.
V.V. Vassiliev S.M. Il’ina V.L. Velichansky 《Applied physics. B, Lasers and optics》2003,76(5):521-523
A miniature high-coherent diode laser was developed. Optical feedback from a high-Q microsphere resonator was used to narrow
the spectrum of the laser, and a nearly half-pitch gradient-index lens served as a coupling element. As estimated from the
variation in frequency-tuning range (chirp-reduction factor) the fast line width of the laser was reduced by more than three
orders. It is remarkable that the system reveals stable single-mode operation at a relatively high feedback level. A tentative
explanation is presented in terms of previously given models.
Received: 8 July 2002 / Revised version: 9 March 2003 / Published online: 24 April 2003
RID="*"
ID="*"Corresponding author. Fax: +7-095/334-0249, E-mail: vvv@okb.lpi.troitsk.ru 相似文献
6.
+ ions. The Ca+ ions are trapped in a miniature rf Paul trap and irradiated by light from a frequency-doubled diode laser at 397 nm and by
light from a diode laser at 866 nm. We are able to cool a single ion and observe its fluorescence continuously with the laser
diode locked to the external frequency-doubling cavity. Quantum jumps in the fluorescence light of a single ion and of a small
cloud of five ions have been induced by driving the “clock” transition at 729 nm. We were able to resolve the influence of
the micromotion on the excitation spectrum of the small ion cloud.
Received: 10 July 1997/Revised version: 17 November 1997 相似文献
7.
An ultra-short-pumped optical dye amplifier operating in the near-IR (720 nm) has been developed. We present an experimental
study of the input–output characteristics of this simple device in a traveling wave collinear configuration. In essence, the
combined effects of the ultrafast nature of the anisotropy induced by the exciting laser pulse along with the short transit
time across the length of the cell allow for optimal output conditions given the number of molecules in the active volume.
Two distinct amplifying regimes have been observed depending on photon density. Typical gain values of 104 of the narrow bandwidth (∼9 nm) subpicosecond output signal were measured. The 8-mm2 beam cross section enables this photon amplifier to be utilized in time-gated imaging applications.
Received: 12 December 2001 / Revised version: 13 May 2002 / Published online: 25 October 2002
RID="*"
ID="*"Corresponding author. Fax: +1-819/564-5442, E-mail: Daniel.Houde@Usherbrooke.ca 相似文献
8.
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
9.
Diode-pumped Cr:LiCAF fs regenerative amplifier system seeded by an Er-doped mode-locked fiber laser
A fs regenerative amplifier based on Cr:LiCAF is demonstrated for the first time. With direct diode pumping, 8 μJ of pulse
energy are obtained directly from the amplifier. When seeded by an Er-doped fiber laser, the amplified seed pulses are compressed
down to 252 fs, limited by residual net third-order dispersion of the compression gratings and intracavity elements. Pulse
broadening due to second- and third-order dispersion is theoretically investigated and compared to experimental results. Dispersion
generated by the geometrical cavity arrangement is measured experimentally.
Received: 19 November 2001 /
Revised version: 28 January 2002 / Published online: 14 March 2002 相似文献
10.
Thorsten Ulm Harry Fuchs Andreas Klehr Edeltraud Gehrig 《Optics Communications》2008,281(8):2160-2166
The amplification of ps and fs pulses with peak powers of up to 4.5 kW has been investigated in a single quantum well InGaAs tapered amplifier. The pulses with durations of 100 fs or 2 ps were generated by a modelocked titanium-sapphire laser. The amplified pulses indicate strong gain saturation and carrier generation due to photon absorption in the laser active region which causes a temporal broadening of the amplified pulses as well as modifications of the optical spectrum. The gain recovery time was measured by a pump-probe experiment. The experimental results are analyzed with respect to the sub-ps gain dynamics which is described by a relaxation time approximation. 相似文献
11.
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
12.
I. Shvarchuck K. Dieckmann M. Zielonkowski J.T.M. Walraven 《Applied physics. B, Lasers and optics》2000,71(4):475-480
We report on master-oscillator power amplification using a broad-area laser diode (BAL) emitting at a wavelength of λ =780 nm.
The master oscillator is an injection-locked single-mode diode laser delivering a seeding beam of 35 mW, which is amplified
in double pass through the BAL up to 410 mW. After beam shaping and spatial filtering by a single-mode fibre we obtain a clean
Gaussian beam with a maximum power of 160 mW. There is no detectable contribution of the BAL eigenmodes in the spectrum of
the output light. This laser system is employed for operation of a 87Rb magneto-optical trap (MOT) and for near-resonant absorption imaging in a Bose-Einstein condensation experiment.
Received: 10 April 2000 / Revised version: 13 June 2000 / Published online: 2 August 2000 相似文献
13.
S. Forget F. Balembois P. Georges P.-J. Devilder 《Applied physics. B, Lasers and optics》2002,75(4-5):481-485
We report on new, simple and efficient multipass amplifiers using prisms or corner cubes to perform several passes in different
planes of incidence. This scheme provides an optimised overlap between the signal passes and the pumped volume. We investigated
our amplification geometry with Nd:YAG and Nd:YVO4 crystals: the use of a low-doped (0.3%) Nd:YVO4 crystal allowed better thermal behaviour and higher performance. We amplified a pulsed microlaser (110 mW of average power
at 1064 nm) and obtained a diffraction-limited output beam with an average power of 5.7 W for 15 W of pump power and a small-signal
gain of 56 dB in a six-pass configuration.
Received: 5 March 2002 / Revised version: 6 June 2002 / Published online: 25 September 2002
RID="*"
ID="*"Corresponding author. Fax: +33-1/6935-8700, E-mail: Sebastien.forget@iota.u-psud.fr 相似文献
14.
Ch. Schwedes E. Peik J. von Zanthier A.Y. Nevsky H. Walther 《Applied physics. B, Lasers and optics》2003,76(2):143-147
A compact, tunable and narrow-bandwidth laser source for blue and ultraviolet radiation is presented. A grating-stabilized
diode laser at 922 nm is frequency-stabilized to below 100 Hz relative to a reference resonator. Injection of the diode-laser
light into a tapered amplifier yields a power of 0.5 W. In a first frequency-doubling stage, more than 200 mW of blue light
at 461 nm is generated by use of a periodically poled KTP crystal. Subsequent second-harmonic generation employing a BBO crystal
leads to about 1 mW of ultraviolet light at 231 nm.
Received: 12 August 2002 / Published online: 15 January 2003
RID="*"
ID="*"Corresponding author. Fax: +49-89/32905-200, E-mail: christian.schwedes@mpq.mpg.de
RID="**"
ID="**"Present address: PTB, Bundesallee 100, 38116 Braunschweig, Germany 相似文献
15.
E. Gehrig O. Hess C. Seibert D. Woll R. Wallenstein 《Applied physics. B, Lasers and optics》2003,76(3):285-288
We theoretically describe and experimentally investigate the spatio-spectral wave mixing of induced and spontaneous emission
in large-area InGaAs-semiconductor laser amplifiers. The dynamic light-matter-coupling is described by a spatially resolved
theory based on Maxwell–Bloch–Langevin equations, taking into account many-body-carrier interactions, energy transfer between
the carrier and phonon systems and, in particular, the spatio-temporal interplay of stimulated and amplified spontaneous emission
and the noise caused by spontaneous emission. Our numerical model reveals the fundamental physical processes which are responsible
for the spectral power distribution of the amplified laser light and predicts the emission properties of high-power semiconductor
laser amplifiers, such as emission spectra and input power–output power characteristics.
Received:30October2002/Revisedversion:21November2002 / Published online: 12 February 2003
RID="*"
ID="*"Corresponding author. Fax: +49-711/6862-349, E-mail: Edeltraud.Gehrig@dlr.de
RID="**"
ID="**"Also at: Institute of Physics, Tampere University of Technology, P.O. Box 692, FIN-33101, Tampere, Finland
RID="***"
ID="***"Present address: Heidelberger Druckmaschinen AG, Speyerer Strasse 6, 69115 Heidelberg, Germany
RID="****"
ID="****"Present address: Lightbit Corporation, 411 Clyde Avenue, Mountain View, CA 94043, USA 相似文献
16.
We investigate the characteristics of Whispering-Gallery(WG)-like modes in a square cavity with posts by employing the two-dimensional (2D) finite-difference time-domain (FDTD) technique combined with the effective index method. The results indicate that the posts can result in mode selection in the WG-like modes. The WG-like modes with odd mode numbers are not much sensitive to the sizes of the posts. However, the quality factor (i.e. Q-factor) of the WG-like modes with even mode numbers decreases sharply with the increasing size of the posts. The decreasing Q-factor is attributed to mode leakage and scattering loss due to the presence of the post. The mode selection increases the mode spacing of square cavity twice in an optimized structure. 相似文献
17.
D. Akitt H. J. J. Seguin M. R. Cervenan S. K. Nikumb 《Applied physics. B, Lasers and optics》1990,51(5):326-328
An on-line, electronic feedback approach for automatic alignment of a laser resonator is described. A measure of the resonator alignment error is derived by partitioning a 1% sample of the laser output into quadrants, and using standard electronic circuits to compare the average power present in each quadrant. A motorized X — Y alignment system is then used to implement the alignment changes required to maintain optimum output quality from the laser. The system is shown capable of stabilizing the output power in each quadrant of the beam to within about 2% of the optimum level. 相似文献
18.
H. R. Telle 《Applied physics. B, Lasers and optics》1989,49(3):217-226
A fast electronic frequency stabilisation scheme is presented which improves the coherence properties of near IR laser diodes substantially. The control loop is effective even under fast, wideband frequency tuning conditions, which opens up new fields of application in spectroscopy, range finding and data communication.Dedicated to Prof. Dr. Herbert Welling on the occasion of his 60th birthday 相似文献
19.
Narrow bandwidth operation of high-power broad-area diode laser using cascaded phase-conjugate injection locking 总被引:1,自引:0,他引:1
H. Horiuchi T. Shimura T. Omatsu O. Matoba K. Kuroda 《Applied physics. B, Lasers and optics》1999,68(5):1021-1025
A broad-area laser is injection-locked by another broad-area laser that is also injection-locked by a single-mode diode laser.
Two double-phase conjugate mirrors of photorefractive BaTaO3 are used to couple the master laser beams to the first slave laser, and the first slave laser output to the second slave
laser. One of the double-phase conjugate mirrors is built up with the beams from two broad-area lasers. Two slave lasers are
oscillating in single longitudinal mode at 808.5 nm and the spectral width is the same as that of the master laser. Final
single-mode output power from the second slave broad-area laser is 840 mW, which is limited by the power of the injection
beam. This work verifies the possibility of the multi-stage cascaded injection locking of high-power diode lasers with phase-conjugate
injection.
Received: 18 November 1998 / Revised version: 29 January 1999 / Published online: 7 April 1999 相似文献
20.
O. Casel D. Woll M. A. Tremont H. Fuchs R. Wallenstein E. Gerster P. Unger M. Zorn M. Weyers 《Applied physics. B, Lasers and optics》2005,81(4):443-446
We report the generation of blue 489-nm picosecond laser pulses by intracavity second-harmonic generation in a mode-locked optically pumped InGaAs vertical-external-cavity surface-emitting laser. Mode locking achieved by a semiconductor saturable absorber mirror generated 5.8-ps-long sech2-shaped pulses at an emission wavelength of 978 nm and a repetition rate of 1.88 GHz. Intracavity frequency doubling in a 5-mm-long lithium triborate crystal generated blue picosecond pulses with a spectral width of 0.15 nm and an average output power of up to 6 mW. 相似文献