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1.
Broadly tunable difference-frequency generation (DFG) in AgGaS2 was achieved by mixing dual-wavelength oscillating pulses from an electronically tuned Ti:sapphire laser with a two-frequency-driven
acousto-optic device. Continuous tuning from 6.5 to 8.5 μm was achieved by simultaneous dual-wavelength-tuned DFG without
crystal rotation. In the dual-pulse oscillation, the shorter and longer wavelength pulses were tuned from 700 to 775 nm and
from 763 to 880 nm, respectively, while keeping the phase-matching relationship for DFG. When crystal rotation was adopted,
however, the tunable output range was extended from 5.3 to 12 μm by tuning the longer wavelength pump pulse, while the shorter
wavelength pulse was fixed.
Received: 18 November 1998 / Revised version: 5 February 1999 / Published online: 26 May 1999 相似文献
2.
W. Shuicai H. Junfang X. Dong Z. Changjun H. Xun 《Applied physics. B, Lasers and optics》2001,72(7):819-821
We have constructed a three-wavelength Ti:sapphire femtosecond laser with an independent tunable wavelength (λ1) and two variable central wavelengths (λ2 and λ3) for use with the multi-excited photosystem II. Stable sub-40-fs pulses are generated. The λ1-wavelength pulses can be tuned independently from 750 nm to 850 nm. The center wavelengths λ2 and λ3 can be varied from 760 nm to 840 nm.
Received: 14 April 2000 / Revised version: 5 September 2000 / Published online: 27 April 2001 相似文献
3.
C. Du Z. Wang J. Liu X. Xu B. Teng K. Fu J. Wang Y. Liu Z. Shao 《Applied physics. B, Lasers and optics》2001,73(3):215-217
We report, for the first time, efficient intracavity second-harmonic generation (SHG) at 1.06 μm in a non-linear optical crystal,
BiB3O6 (BIBO), at a type-I phase-matching direction of (θ,ϕ)=(168.9°,90°), performed with a LD end-pumped cw Nd:YVO4 laser. A cw SHG output power of 364 mW has been obtained using a 1.9-mm-thick BIBO crystal. The optical conversion efficiency
was 12.2% and the corresponding effective intracavity SHG efficiency was determined to be 32.4%. It was found that the intracavity
SHG efficiency is greater than that obtained with a type-II phase-matching KTiOPO4 (KTP) crystal with a thickness of 3 mm. The effective non-linear optical coefficient (deff) ratio of BIBO to that of KTP, determined experimentally, is 1.23:1.
Received: 7 May 2001 / Revised version: 6 July 2001 / Published online: 19 September 2001 相似文献
4.
The influence of an external field on photorefractive recording in Sn2P2S6 (SPS) crystals is studied. A large gain factor of more then 15 cm-1 is achieved for a grating spacing of 12 μm at λ=0.9 μm. For an applied field exceeding ±200 V/cm a switching of the beam
coupling direction is detected, exhibiting a pronounced hysteresis.
Received: 25 October 2000 / Revised version: 18 January 2001 / Published online: 21 March 2001 相似文献
5.
Mid-infrared trace gas detection using continuous-wave difference frequency generation in periodically poled RbTiOAsO4 总被引:1,自引:0,他引:1
A tunable mid-infrared continuous-wave (cw) spectroscopic source in the 3.4–4.5 μm region is reported, based on difference
frequency generation (DFG) in a quasi-phase-matched periodically poled RbTiOAsO4 (PPRTA) crystal, DFG power levels of 10 μW were generated at approximately 4 μm in a 20-mm long PPRTA crystal by mixing two
cw single-frequency Ti:Al2O3 lasers operating near 713 nm and 871 nm, respectively, using a laser pump power of 300 mW. A quasi-phase-matched infrared
wavelength-tuning bandwidth (FWHM) of ∼12 cm-1 and a temperature tuning rate of 1.02 cm-1/°C were achieved. Experimental details regarding the feasibility of trace gas detection based on absorption spectroscopy
of CO2 in ambient air using this DFG radiation source are also described.
Received: 23 October 2000 / Revised version: 22 January 2001 / Published online: 27 April 2001 相似文献
6.
G. Schreiber H. Suche Y.L. Lee W. Grundkötter V. Quiring R. Ricken W. Sohler 《Applied physics. B, Lasers and optics》2001,73(5-6):501-504
Using an FM-mode-locked Ti:Er:LiNbO3 waveguide laser as the fundamental source, wavelength conversion by cascaded χ(2):χ(2)-difference frequency generation with a conversion efficiency of up to +3(-4.6) dB was demonstrated at a pulse repetition
rate of about 2 (10) GHz. In addition, multi-channel conversion was demonstrated with a fully packaged wavelength converter
using a continuous fundamental source.
Received: 29 May 2001 / Revised version: 10 August 2001 / Published online: 2 November 2001 相似文献
7.
We describe a laser system that readily provides radiation tunable from 2 μm in the infra-red to 35 nm in the extreme ultraviolet
spectral range. The broad spectral range is covered through a range of non-linear processes such as Raman shifting and high-order
harmonic generation. Pulses with duration of tens of picoseconds are obtained. The relative bandwidth of the radiation is
δλ/λ=10-4, comparable with what can be achieved by using high-resolution monochromators at state-of-the-art synchrotron beamlines.
We discuss different methods for characterising the radiation in this wide wavelength regime. We also discuss the capabilities
of the system from the measured parameters.
Received: 12 December 2000 / Revised version: 8 March 2001 / Published online: 27 April 2001 相似文献
8.
Efficient and compact intracavity-frequency-doubled Nd:GdVO4/KTP laser end-pumped by a fiber-coupled laser diode 总被引:2,自引:0,他引:2
D.Y. Shen H.R. Yang J.G. Liu S.C. Tam Y.L. Lam W.J. Xie J.H. Gu K. Ueda 《Applied physics. B, Lasers and optics》2001,72(3):263-266
A compact and efficient diode-pumped intracavity-frequency-doubled Nd:GdVO4/KTP green laser is demonstrated with a flat–flat cavity design. With a 1.3 at. % Nd3+-doped GdVO4 crystal and pumped at the weak-absorption peak of 806 nm, the second-harmonic output power at 532 nm was measured to be 1.95 W
at an incident pump power of 8.4 W, corresponding to an optical conversion efficiency of 23.2%. The output characteristic
at the fundamental wavelength of 1.063 μm was investigated with two different pump wavelengths. More than 4.5-W output power
was generated when the laser was pumped at 806.2 nm.
Received: 26 July 2000 / Revised version: 18 September 2000 / Published online: 7 February 2001 相似文献
9.
C. Du Z. Wang J. Liu X. Xu K. Fu G. Xu J. Wang Z. Shao 《Applied physics. B, Lasers and optics》2002,74(2):125-127
Intracavity sum-frequency mixing of 1.06 μm and 532 nm in YCa4O(BO3)3 (YCOB) crystals cut for different type-I phase-matching directions of (θ,ϕ)=(106°,77.2°), (111°, 79.6°) and (65°, 82.8°)
was investigated in a compact diode-end-pumped acousto-optical Q-switched Nd:YVO4/KTP laser formed with a three-mirror folded resonator. The maximum 355-nm average output power of 124 mW was obtained in
the phase-matching direction of (106°, 77.2°) with a pump-to-ultraviolet conversion efficiency of 3.3% at the repetition frequency
of 20 kHz.
Received: 17 September 2001 / Revised version: 27 November 2001 / Published online: 17 January 2002 相似文献
10.
Low-threshold mid-infrared optical parametric oscillation in periodically poled LiNbO3 synchronously pumped by a Ti:sapphire laser 总被引:1,自引:0,他引:1
We report the generation of tunable high-repetition-rate optical pulses in the mid-infrared using synchronously pumped parametric
oscillation in periodically poled LiNbO3 (PPLN). Using a Kerr-lens-mode-locked Ti:sapphire laser as the pump source and a PPLN crystal incorporating grating periods
of 21.0–22.4 μm, we have achieved wavelength conversion in the -–4 6μm spectral range in the mid-infrared. The use of a semi-monolithic
cavity design and hemispherical focusing has permitted pulse generation in the strong idler absorption region of PPLN, resulting
in a simple, compact, all-solid-state configuration with a pump power threshold as low as 17 mW and mid-infrared idler powers
of up to 64 mW at 9% extraction efficiency. Signal output powers of up to 280 mW at 35% extraction efficiency are available
over the -–1.004 1.140μm spectral range at 80.5 MHz and pulse repetition rates at harmonics of the fundamental frequency up
to 322 MHz have also been obtained.
Received: 5 December 2000 / Revised version: 23 January 2001 / Published online: 27 April 2001 相似文献
11.
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
12.
E. I. Salamatov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(11):1442-1447
Peculiarities of the kinetics of weakly nonequilibrium thermal phonons (λph = 10−50 nm) in nanodispersed ceramics are investigated. The features of the phonon spectrum in the wavelength range λph ∼ R
g (where R
g is the average size of a ceramic grain) are studied. The conditions yielding the formation of a gap in the phonon spectrum
of nanodispersed materials are analyzed. It is shown that the presence of inclusions with characteristic sizes smaller than
the grain size of the parent ceramic material (pores, inclusions of other phases) shifts the gap toward the high-frequency
range of the phonon spectrum. Peculiarities of the transport of nonequilibrium phonons during the transition from nano- to
microdispersed sizes of the ceramic structure are analyzed. 相似文献
13.
A. Apolonskii S. Baluschev U. Hinze E. Tiemann B. Wellegehausen 《Applied physics. B, Lasers and optics》1997,64(4):435-442
In a double-Λ level configuration of Na2 molecules, involving rotational–vibrational levels of the X, A and B bands, continuous resonant frequency mixing ω4=ω1−ω2+ω3 is demonstrated. A DCM dye laser at 661 nm (λ1) pumps a molecular Raman laser at 746 nm (λ2) in a sodium heatpipe, which is used to generate the molecular vapour. In the same heatpipe, both fields are mixed with the
radiation of an argon-ion laser at 514 nm (λ3) to generate up-converted laser radiation at 473 nm (λ4). For laser powers of 200 mW (λ1), 700 mW (λ2, internal power) and 140 mW (λ3), an output power of 120 μW (λ4) has been achieved. Dependences of the generated radiation on the pump fields (powers and detunings) and polarization features
are presented; influences of coherent coupling and population transfer mechanisms are discussed.
Received: 7 October 1996 相似文献
14.
N.A. Papadogiannis C. Kalpouzos E. Goulielmakis G. Nersisyan D. Charalambidis F. Augé F. Weihe Ph. Balcou 《Applied physics. B, Lasers and optics》2001,73(7):687-692
A compact, versatile table-top kilohertz source of coherent extreme-ultraviolet (XUV) radiation in the wavelength region 18–100 nm,
based on high-order harmonic generation from noble gases induced by a 40-femtosecond Ti:sapphire laser system, is presented.
The XUV beamline delivers at its output 108 photons/s at a wavelength of 23 nm. The monochromatized XUV radiation is directly focused onto a 10-2-mm2 spot by a toroidal grating, allowing one to reach intensities higher than 106 W/cm2. Optimization results are presented for a new XUV-generating geometry, utilizing a ‘semi-infinite’ quasi-static gas cell
and strong focusing. In those conditions, we observe an anomalous inversion between the cutoffs of argon and krypton, with
the krypton spectrum extending to much higher orders than expected in an adiabatic limit.
Received: 9 July 2001 / Revised version: 1 August 2001 / Published online: 7 November 2001 相似文献
15.
Optical parametric oscillators for high pulse energy and high average power operation based on large aperture periodically poled KTP and RTA 总被引:3,自引:0,他引:3
M. Peltz U. Bäder A. Borsutzky R. Wallenstein J. Hellström H. Karlsson V. Pasiskevicius F. Laurell 《Applied physics. B, Lasers and optics》2001,73(7):663-670
We report on optical parametric oscillators (OPOs) based on large aperture periodically poled KTiOPO4 (PPKTP) and RbTiOAsO4 (PPRTA) pumped with high pulse energy and high average power Q-switched solid-state lasers. The OPOs were pumped with 1064-nm
pulses of a diode-pumped Nd:YVO4 laser at 20 kHz repetition rate. The emitted signal wavelengths were 1.72 μm and 1.58 μm and the idler wavelengths were 2.79 μm
and 3.26 μm, respectively. Pumping the PPKTP OPO with 7.2 W and the PPRTA OPO with 8 W average power, 2 W and 1.3 W total
OPO output powers were generated. Two-dimensional measurements of the total OPO output power, the signal wavelength and the
signal bandwidth in dependence on the crystal location indicated a good uniformity of the quasiphasematching structure over
the entire 3-mm-thick crystals. This allowed pumping with larger pump beams and therefore with pulse energies of tens of millijoules.
Pumping with different flash-lamp-pumped lasers, good OPO performance and high output pulse energies could be achieved for
all pump lasers. Maximum input pulse energies of 56 mJ gave output pulse energies of as much as 18 mJ. The temperature tuning
behaviors of both OPOs were measured, showing excellent agreement with calculated temperature tuning curves. New equations
for temperature dispersion in RTA are presented. These results show that large-aperture PPKTP and PPRTA crystals are well
suited for tunable nanosecond OPO operation with multi-watt average pump power and several tens of millijoules pump pulse
energies.
Received: 7 September 2001 / Published online: 7 November 2001 相似文献
16.
Y. Wang C. Zhang Y. Song K. Yang G. Fang X. Xin 《Applied physics. B, Lasers and optics》2002,74(1):43-46
The nonlinear absorption and refraction of the clusters [MoS4Cu4Br2(py)6] and [Et4N]2[MoS4Cu4(SCN)4(2-pic)4] have been investigated using the z-scan technique with a ns laser at 532 nm wavelength. They have the same planar ‘open’
structures and the same skeleton metal atoms; the only difference is that the former has halogen ligands while the latter
possesses pseudo-halogen groups – SCN – as ligands. Alteration of nonlinear refractive index and enhancement of nonlinear
absorption were found in these two clusters. A steady state model of excited state nonlinear refraction was proposed to explain
this phenomenon.
Received: 12 June 2001 / Revised version: 4 September 2001 / Published online: 29 November 2001 相似文献
17.
By analogy with the classic effect of the double refraction of light, we investigate the relevant effect of an electron entering
from the Non-Rashba region to the Rashba region in two-dimensional systems. It is shown that the effect of electronic double
refraction is determined by a combined parameter γ = m
*
λ
F
α/2πħ2, rather than both the Rashba coefficient α and wavelength λ
F of a Fermi electron, separately. For the case of normal incidence, the analytical expressions for the wavefunction of the
electron are presented; it is predicted that the Rashba spin-orbit coupling can induce a current perpendicular to the normal
incident direction of the electron. Moreover, the general case of incident electron with any given momentum and spin state
are studied numerically in detail, including the abrupt changes of spin direction and the two-step characters for reflection.
相似文献
18.
D. Mazzotti P. De Natale G. Giusfredi C. Fort J.A. Mitchell L.W. Hollberg 《Applied physics. B, Lasers and optics》2000,70(6):747-750
We report difference-frequency generation (DFG) in periodically poled lithium niobate (PPLN) around 4.25 μm using a cw Nd:YAG
and an injection-locked diode laser. This system provides a narrow linewidth source at 4.25 μm with near-shot-noise-limited
operation. A conversion efficiency close to the theoretical limit is obtained. Detection of CO2 absorption spectra is demonstrated and further improvements and applications to high sensitivity spectroscopy are discussed.
Received: 12 August 1999 / Revised version: 21 January 2000 / Published online: 24 March 2000 相似文献
19.
We report, for the first time, an efficient intra-cavity second-harmonic generation (SHG) at 1084 nm in a nonlinear optical crystal, BiB3O6(BIBO) at the direction of (θ, ?) = (170.1°, 90°), performed with a LD end-pumped cw Nd:YVO4 laser. With 590 mW diode pump power, a continuous-wave (cw) SHG output power of 19 mW at 542 nm yellow-green color has been obtained using a 1.5 mm-thick BIBO crystal. The optical conversion efficiency was 3.22%. It was found that the output wavelength could be 532 nm, 537 nm or 542 nm according to regulating the angle of BIBO. 相似文献
20.
J. Liu X. Xu C.Q. Wang S. Zhang J. Wang H. Chen Z. Shao M. Jiang 《Applied physics. B, Lasers and optics》2001,72(2):163-166
The characteristics of intracavity second-harmonic generation (SHG) at 1.06 μm in GdCa4O(BO3)3 (GdCOB) crystals cut for different type I phase-matching (PM) directions of (θ,φ)=(66.8°, 132.3°); (19.4°, 0°); (90°, 46°)
have been investigated. It was found that the intracavity SHG was significantly efficient in the PM direction of (66.8°, 132.3°),
and that the intrinsic lower effective nonlinear coefficient (deff) was responsible for the less-efficient SHG in the other two directions. A maximum CW SHG output power of 2.81 W was obtained
with an optical conversion efficiency of 18.7%, while the corresponding effective intracavity SHG efficiency was determined
to be 41.3%. The intracavity SHG efficiency of GdCOB has been found to reach two-thirds of that obtained with type II phase-matching
KTiOPO4 (KTP).
Received: 26 April 2000 / Revised version: 3 July 2000 / Published online: 5 October 2000 相似文献