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1.
C. Drag I. Ribet M. Jeandron M. Lefebvre E. Rosencher 《Applied physics. B, Lasers and optics》2001,73(3):195-200
The temporal behavior of a nanosecond pulsed singly resonant periodically poled lithium niobate optical parametric oscillator
has been studied both theoretically and experimentally. Taking into account the cylindrical symmetry of the system, a numerical
model based on the Hankel transform has been developed. Good agreement is obtained between experiment and simulation. Moreover,
the computation time is reduced roughly by a factor of 60 compared to the usual simulation software.
Received: 23 April 2001 / Published online: 19 September 2001 相似文献
2.
K.I. Petsas A. Gatti L.A. Lugiato C. Fabre 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(3):501-512
We investigate the spatial behaviour of the quantum-noise-reduction spectrum of the vacuum state emitted by a degenerate optical
parametric oscillator below threshold. In view of possible experimental implementations, we consider a mode-degenerate resonator
and two matching lenses and show that, for the realistic case of a finite-width pump, significant level of squeezing can be
observed in a very small region of the beam.
Received 25 September 2002 Published online 11 February 2003 相似文献
3.
We report on a femtosecond optical parametric oscillator (OPO) with a repetition rate of 1 GHz, which is 12 times that of
the pump laser used. We also introduce a novel method for operating an OPO with a high harmonic repetition rate which is not
determined by the cavity length of the OPO, but rather the cavity length difference between the OPO and its pump laser. Operation
of an OPO at 4-times the harmonic repetition rate has been carried out to show the feasibility of this method. The new approach
paves the way for constructing a femtosecond OPO working at repetition rates of 10 GHz, or higher, when the pump laser used
has a relatively low repetition rate.
Received: 26 October 2001 / Revised version: 11 Januar 2002 / Published online: 14 March 2002 相似文献
4.
We compare the Q parameter obtained from scalar, semi-analytical and full vector models for realistic transmission systems. One set of systems is operated in the linear regime, while another is using solitons at high peak power. We report in detail on the different results obtained for the same system using different models. Polarisation mode dispersion is also taken into account and a novel method to average Q parameters over several independent simulation runs is described. 相似文献
5.
Received: 11 March 1998/Revised version: 1 April 1998 相似文献
6.
O. Prakash H.-H. Lim B.-J. Kim K. Pandiyan M. Cha B. K. Rhee 《Applied physics. B, Lasers and optics》2008,92(4):535-541
Collinear broadband optical parametric generation (OPG) using periodically poled lithium niobate (PPLN) crystals were designed
and experimentally demonstrated with the quasi-phase matching (QPM) periods of 21.5, 24.0, and 27.0 μm. The broad gain bandwidth was accomplished by choosing a specific set of the period and the pump wavelength that allows
the group velocities of the signal and the idler to match close to the degeneracy point. OPG gain bandwidth and also the spectral
region could be controlled by proper design of QPM period and pump wavelength. The total OPG gain bandwidth of 600, 900, and
1200 nm was observed for the PPLN devices with QPM periods of 21.5, 24.0, and 27.0 μm, respectively. We have also observed multiple color visible generation whenever the OPG spectrum was significantly broad.
From the visible peaks of the three PPLN samples, it is found that broad gain bandwidth is crucial in the temperature-insensitive
collinear simultaneous RGB generation from a single crystal. 相似文献
7.
A. H. Bhuiyan D. R. Richardson S. V. Naik R. P. Lucht 《Applied physics. B, Lasers and optics》2009,94(4):559-567
An injection-seeded optical parametric generator (OPG), coupled with three pulsed dye amplification (PDA) stages, was shown
to produce tunable, narrow linewidth laser radiation. The OPG was composed of a pair of beta barium borate (β-BBO) crystals and pumped by the third harmonic (355 nm) output of a seeded Nd:YAG laser. The OPG was injection-seeded at
the idler wavelength (824 nm) using an external cavity diode laser (ECDL) with a mode-hop-free tuning range of 20 GHz. Using
the PDA stages, the OPG output signal (624 nm) was amplified to 19 mJ/pulse, while maintaining a spectral linewidth of approximately
160 MHz at full-width-half-maximum (FWHM) which was within a factor of 2 of the Fourier limit. A system of lenses and apertures
was used to minimize amplified spontaneous emission (ASE) in the PDA stages. Using the OPG/PDA system, two-photon laser-induced
fluorescence measurements of atomic oxygen were performed by sum-frequency-mixing the 624-nm beam with the third harmonic
output of the seeded Nd:YAG laser to generate approximately 1 mJ/pulse of ultraviolet radiation near 226 nm. Voigt line shapes
were found to be in good agreement with oxygen atom spectra in atmospheric-pressure, laminar, counter-flow flames; the magnitude
of Doppler and collisional broadening was approximately the same. The measured O-atom concentration profile was found to compare
well with that calculated using an opposed-flow flame code. 相似文献
8.
We demonstrate that for a given pump source, there is an optimum pump threshold to achieve the maximum single-frequency output
power in singly resonant optical parametric oscillators. Therefore, cavity losses and parametric amplification have to be
adjusted. In particular, continuous-wave output powers of 1.5 W were achieved with a 2.5 cm lithium niobate crystal in comparison
with 0.5 W by a 5 cm long crystal within the same cavity design. This counter-intuitive result of weaker amplification leading
to larger powers can be explained using a model from L.B. Kreuzer (Proc. Joint Conf. Lasers and Opt.-Elect., p. 52, 1969). Kreuzer also states that single-mode operation is possible only up to pump powers which are 4.6 times the threshold value.
Additionally, implementing an outcoupling mirror to increase losses, single-frequency waves with powers of 3 W at 3.2 μm and 7 W at 1.5 μm could be generated simultaneously. 相似文献
9.
M. Vainio J. Peltola S. Persijn F. J. M. Harren L. Halonen 《Applied physics. B, Lasers and optics》2009,94(3):411-427
Stability and tuning characteristics of continuous-wave optical parametric oscillators (CW OPOs) are affected by various thermal
effects arising from optical absorption in nonlinear crystals. In this paper, we present an experimental study of such effects
in a singly resonant CW OPO. The OPO operates in the 3-μm mid-infrared region and it is based on a MgO-doped periodically
poled lithium niobate crystal. We focus our study on two thermally induced phenomena that have been recently reported to exist
in singly resonant CW OPOs: optical bi-stability and thermal self-locking. Thermal self-locking effect, which is known to
alter the stability and tuning properties of doubly and triply resonant CW OPOs, is shown to be also of importance in singly
resonant OPOs. We report the stability and tuning characteristics of a thermally loaded OPO and discuss a simple temperature-tuning
method that can be used to scan the OPO idler frequency continuously over several THz. 相似文献
10.
In this article, we present studies on therahertz (THz) wave generation and frequency up-conversion in a periodically poled lithium niobate (PPLN) crystal. A frequency at 1.37 THz was generated as femtosecond pump pulses passed through a PPLN crystal with grating periods of 30 μm. The pump-induced THz wave interacts with the probe wave in the crystal by frequency mixing. The frequency up-converted THz wave is easily detected by a normal photodiode. A new scheme for generation and detection of THz wave in one non-linear crystal was proposed. 相似文献