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1.
T. Andres P. Haag S. Zelt J.-P. Meyn A. Borsutzky R. Beigang R. Wallenstein 《Applied physics. B, Lasers and optics》2003,76(3):241-244
A synchronously pumped femtosecond optical parametric oscillator based on congruent MgO-doped periodically poled lithium niobate
(c-MgO:PPLN) is reported. The system, operating at room temperature, was pumped by a mode-locked Ti:sapphire laser. The wavelengths
of the signal and idler waves were tuned from 870 nm to 1.54 μm and 1.58 to 5.67 μm, respectively, by changing the pump wavelength,
the grating period or the cavity length. Pumped by 1.1 W of 755 nm laser radiation, the OPO generated 310 mW of 1080 nm radiation.
This signal output corresponds to a total conversion efficiency of 50%. Without dispersion compensation the OPO generated
phase-modulated signal pulses of 200 fs duration. Besides the OPO of c-MgO:PPLN, an OPO of stoichiometric (s) MgO:PPLN was
investigated. Because of the reduced sensitivity to photorefractive damage, both crystals allowed efficient OPO operation
at room temperature.
Received: 19 August 2002 / Revised version: 11 December 2002 / Published online: 19 March 2003
RID="*"
ID="*"Corresponding author. Fax: +49-631/205-3906, E-mail: andres@physik.uni-kl.de 相似文献
2.
Generation of Femtosecond Laser Pulse at 1.43 GHz from an Optical Parametric Oscillator Based on LBO Crystal 下载免费PDF全文
《中国物理快报》2019,(12)
A femtosecond LBO optical parametric oscillator(OPO) with widely adjustable repetition rate by fractionally decrement of the cavity length is demonstrated. The repetition rate of 755 MHz to 1.43 GHz at an interval of 75.5 MHz is realized, which is 10 to 19 times that of the pump laser. The properties of output signal at 750 nm at different repetition rates are studied. The power of signal decreases with increasing the repetition rate. The maximum power of 194 mW at the repetition rate of 755 MHz and the minimum power of 22 mW at repetition rate of 1.43 GHz for the signal at 750 nm are obtained for the pump power of 3 W. 相似文献
3.
Single axial mode operation (<200 MHz optical bandwidth) of a high repetition rate periodically poled lithium niobate optical
parametric oscillator (OPO) has been obtained at signal wavelengths between 1.46 μm and 1.64 μm. OPO signal slope efficiencies
of 35% have been measured for repetition rates of 5–20 kHz. Single mode operation required spectral narrowing of both the
pump laser and the OPO. A simple technique of prelase Q-switching was implemented to reduce the optical bandwidth of the cw diode-pumped Nd:YAG pump laser to <1 GHz. A single intracavity
étalon was then sufficient to ensure single frequency oscillation of the OPO signal. The OPO output was stable with a smooth
spatial profile and an M
2 value of 1.3.
Received: 29 September 1999 / Published online: 27 January 2000 相似文献
4.
M.E. Klein A. Robertson M.A. Tremont R. Wallenstein K.-J. Boller 《Applied physics. B, Lasers and optics》2001,73(1):1-10
We theoretically and experimentally investigate wavelength tuning of synchronously pumped optical parametric oscillators (OPOs)
on changing the cavity length or the pump-repetition rate. Conditions for rapid and wide-range wavelength access are derived.
Using an OPO pumped directly by a mode-locked diode-laser master-oscillator power-amplifier (MOPA) system, an all-electronically
controlled access to near- and mid-infrared wavelengths is demonstrated. The singly (signal) resonant OPO is based on periodically
poled lithium niobate (PPLN) and emits 8 ps idler pulses at a repetition rate of 2.5 GHz in the wavelength range 1986 to 2348 nm
(signal: 1530 to 1737 nm). Wavelength tuning over 114 nm (signal) and 189 nm (idler) is achieved solely by electronically
varying the repetition rate of the diode-laser oscillator over 720 kHz. By controlling the repetition rate with a programmable
driver, an arbitrary emission sequence of the OPO on two wavelength channels is generated, with access times as short as 10 μs.
11 OPO wavelengths equally spaced in the range 1627–1689 nm (signal) or 2054–2154 nm (idler) could be addressed.
Received: 6 September 2000 / Revised version: 16 March 2001 / Published online: 23 May 2001 相似文献
5.
Synchronously Pumped Femtosecond Optical Parametric Oscillator Based on MgO-Doped Periodically Poled LiNbO3 下载免费PDF全文
We report a femtosecond optical parametric oscillator based on MgO-doped PPLN synchronously pumped by a mode-locked Ti:sapphire laser. The wavelengths of the signal and idler are continuously tuned from 1100 to 1300hm and from 2080 to 2930nm, respectively, by changing the pump wavelength and the OPO cavity length. The maximum signal output power of 130mW at the wavelength of 1225nm is obtained, pumped by 900roW of 800hm laser radiation. This corresponds to a total conversion efficiency of 22.1%. The signal pulse duration is measured to be 167fs by intensity autocorrelation with chirped mirrors for intracavity dispersion compensation. 相似文献
6.
We report on an optical parametric amplifier (OPA) based on two potassium titanyl phosphate (KTP) crystals in a walk-off compensating
geometry. An Nd:YLF regenerative amplifier at a 1-kHz repetition rate serves as the pump source. The seed beam is delivered
by a synchronously pumped frequency-stabilized optical parametric oscillator (OPO) based on periodically poled lithium niobate
(PPLN). At pump intensities of about 7 GW/cm2 large amplification factors of more than 104 were achieved, resulting in pulse energies of more than 450 μJ and 350 μJ for the signal and idler pulses, respectively,
at a 1-kHz repetition rate. In the saturation regime the time–bandwidth product increases from two to three times the Fourier
limit, with a pulse duration of 105 ps and a bandwidth of 12.7 GHz at the highest intensities employed.
Received: 2 November 2001 / Published online: 14 March 2002 相似文献
7.
The first-Stokes conversion efficiency for a stimulated Raman scattering (SRS) is usually very low in gaseous oxygen media. In 3.0 Mpa O2, a single longitudinal mode second harmonic Nd:YAG laser pump source gives a typical vibrational first-Stokes conversion efficiency of only 2.5%, In comparison, the accompanying stimulated Brillouin scattering (SBS) attains a reflectivity of 67%. However, by seeding an OPO beam into the Raman cavity, the first-Stokes photon conversion efficiency now attains a peak value of 54%, while the SBS reflectivity reduces to 5% in a 6.1 Mpa 41:59 O2/ He mixture. This 54% efficiency was obtained for a seeder laser pulse-width less than one half that of pump laser (6.8 ns). A first-Stokes peak power conversion efficiency as high as 88% has been obtained when the pump and seeder pulse peaks coincide. So, we may expect a higher first-Stokes photon conversion efficiency if the seeder pulse-width can be made equal to or larger than that of the pump pulse. On the other hand, the beam quality of the first-Stokes in an O2/ He mixture excels that of the pump laser for a seeder energy of 5 mJ and pump energy of 50 mJ. However, at pump energies higher than 105 mJ and a pump laser repetition rate of 10 Hz, the thermal defocusing effect worsens the first-Stokes beam quality. This thermal defocusing effect is a result of the Raman heat release and could be eliminated by fast circulating and cooling the Raman gas medium. 相似文献
8.
Tuning and stability of a continuous-wave mid-infrared high-power single resonant optical parametric oscillator 总被引:1,自引:0,他引:1
M.M.J.W. van Herpen S. Li S.E. Bisson S. te Lintel Hekkert F.J.M. Harren 《Applied physics. B, Lasers and optics》2002,75(2-3):329-333
A 2.2-W continuous-wave, continuously tunable, single-frequency OPO has been developed in the 3.0–3.8 μm wavelength range
for the detection of molecular trace gasses. The oscillation threshold, output power and stability of the single resonant
OPO were improved by optimizing pump beam waist and OPO cavity length. Both air-spaced and solid etalons were tested to frequency
stabilize and tune the OPO, from which the solid etalon gave a better performance. Temperature oscillations in the PPLN crystal
caused oscillations in the idler wavelength of less than 200 MHz over 300 s; the short-term stability was less than 3 MHz
over 1 s. The high laser power, in combination with photoacoustic spectroscopy, achieved a detection limit of 10 parts-per-trillion
for ethane in nitrogen.
Received: 9 April 2002 / Revised version: 14 June 2002 / Published online: 2 September 2002
RID="*"
ID="*"Corresponding author. Fax:+31-24/3653311, E-Mail: maartenh@sci.kun.nl 相似文献
9.
We demonstrate a harmonically pumped femtosecond optical parametric oscillator(OPO)laser using a frequency-doubled mode-locked Yb:KGW laser at a repetition rate of 75.5 MHz as the pump laser.Based on a bismuth borate nonlinear crystal,repetition rates up to 1.13 GHz are realized,which is 15 times that of the pump laser.The signal wavelength is tunable from 700 nm to 887 nm.The maximum power of the signal is 207 m W at the central wavelength of 750 nm and the shortest pulse duration is 117 fs at 780 nm.The beam quality(M^2 factor)in the horizontal and vertical directions of the output beam are 1.077 and 1.141,respectively. 相似文献
10.
We report passive harmonic mode locking of a high-power Yb-doped double-clad fiber laser. 680-fs, 48-pJ pulses are emitted at the repetition rate of 2.13 GHz, while the free spectral range of the cavity is 23.4 MHz. Results indicate a supermode suppression of more than 25 dB. 相似文献
11.
High-power picosecond LiB3O5 optical parametric oscillators tunable in the blue spectral range 总被引:2,自引:0,他引:2
The paper reports on an experimental investigation and numerical analysis of noncritically and critically phasematched LiB3O5 (LBO) optical parametric oscillators (OPOs) synchronously pumped by the third harmonic of a cw diode-pumped mode-locked Nd:YVO4 oscillator–amplifier system. The laser system generates 9.0 W of 355-nm mode-locked radiation with a pulse duration of 7.5 ps
and a repetition rate of 84 MHz. The LBO OPO, synchronously pumped by the 355-nm pulses, generates a signal wave tunable in
the blue spectral range 457–479 nm. With a power of up to 5.0 W at 462 nm and 1.7 W at 1535 nm the conversion efficiency is
74%. The OPO is characterized experimentally by measuring the output power (and its dependence on the pump power, the transmission
of the output coupler and the resonator length) and the pulse properties (such as pulse duration and spectral width). Also
the beam quality of the resonant and nonresonant waves is investigated. The measured results are compared with the predictions
of a numerical analysis for Gaussian laser and OPO beams. In addition to the blue-signal output visible-red 629-nm radiation
is generated by sum-frequency mixing of the 1.535-μm infrared idler wave with the residual 1.064-μm laser radiation. A power
of 1.25 W of 1.535-μm idler radiation and 5.7 W of 1.064-μm laser light generated a red 629-nm output power of 2.25 W.
Received: 2 February 2000 / Revised version: 28 July 2000 / Published online: 22 November 2000 相似文献
12.
We report on an optical parametric oscillator (OPO) that is synchronously pumped directly by a diode laser. This laser is an actively mode-locked master-oscillator power-amplifier system that produces 20-ps pulses at 927 nm with a repetition rate of 2.5 GHz and an average power of 0.9 W. The OPO, which is a singly resonant device based on periodically poled lithium niobate, generates 7.8-ps pulses. The OPO threshold is 300 mW of average pump power, and the maximum average idler output power is 78 mW at a wavelength of 2100 nm. By changing the crystal temperature we can wavelength tune the output in the ranges 1530-1737 nm (signal) and 1986-2348 nm (idler). Rapid wavelength tuning of the OPO over 46 nm (signal) and 74 nm (idler) is achieved through tuning the cavity length over 28 microm by use of a piezoelectric transducer. 相似文献
13.
We demonstrate a harmonic mode-locked ytterbium-doped fibre ring laser, which consists of a polarization-sensitive isolator, two polarization controllers, two 976nm laser diodes as the pump source and a two-segment ytterbium-doped fibre. Utilizing an additive pulse mode-locked technique based on nonlinear polarization evolution, the ytterbium-doped fibre laser can operate in mode-locked state by adjusting the position of polarization controllers. The cavity fundamental repetition rate is 23.78 MHz. We also observe the second- and third-harmonic mode locking in the normal dispersion region, and their repetition rates are 47.66 MHz and 71.56 MHz, respectively. Over-driving of the saturable absorber in the harmonic mode-locking pulse is analysed and discussed in detail. 相似文献
14.
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
15.
T.V. Andersen J. Thogersen S.R. Keiding J.J. Larsen 《Applied physics. B, Lasers and optics》2003,76(6):639-644
We demonstrate intracavity frequency doubling of a standard femtosecond Ti:sapphire oscillator. The cavity is extended with
a pair of focusing mirrors and a 0.5-mm-thick BBO crystal. We achieve a repetition rate of 50 MHz and simultaneously generate
22 mW of 55-fs pulses at 810 nm and 200 mW of 73-fs pulses at 405 nm, which corresponds to 4 nJ per pulse. We create a total
of 330-mW, 405-nm light when pumping the Ti:sapphire crystal with 5.7 W from an Ar-ion laser, corresponding to a conversion
efficiency of 5.7%. No saturation is found, which implies that higher outputs can be achieved with higher pump rates. Preliminary
results from the use of blue pulses as pump in an optical parametric amplifier seeded by pulses from a photonic crystal fiber
are presented.
Received: 27 January 2003 / Revised version: 27 March 2003 / Published online: 12 May 2003
RID="*"
ID="*"Corresponding author. Fax: +45-861/96199, E-mail: tva@chem.au.dk 相似文献
16.
针对常规连续激光泵浦钛宝石激光振荡器不能自启动锁模的缺点,采用倍频飞秒光纤激光同步泵浦,通过调节振荡器腔长与泵浦腔长匹配,实现了飞秒钛宝石激光的自启动锁模。实验中采用3.4 W的倍频掺镱光纤激光同步泵浦钛宝石激光振荡器,获得了平均功率大于130 mW、重复频率75 MHz、光谱宽度大于47 nm、脉冲宽度17 fs的锁模脉冲输出,不仅能够稳定可靠地实现自启动锁模,解决了常规钛宝石激光振荡器锁模启动的困难,而且还具有同步输出1040,800,520 nm三束飞秒激光的特点,为进一步开展飞秒激光相干合成以及光参量放大等研究提供了优势基础。 相似文献
17.
A simple experimental technique is presented capable of separating the contribution of purely optical Kerr effects from that
of thermo-optical effects in the nonlinear response of materials under high-repetition-rate laser irradiation. The technique
has been realized by combining the single-beam Z-scan method with the single-beam thermal lens measurement method. We demonstrate
this technique by analysing the nonlinear response at 770 nm of CS2 which exhibits cumulative thermal effects when irradiated by very intense femtosecond laser pulses at a 76-MHz repetition
rate.
Received: 3 November 1998 / Revised version: 4 January 1999 / Published online: 2 June 1999 相似文献
18.
4 (KTA) optical parametric oscillator (OPO) synchronously pumped by a cw diode-pumped mode-locked Nd:YVO4 oscillator–amplifier system. The laser system (pumped by 84 W of cw 808-nm diode radiation) generates 7-ps-long pulses at
1.064 μm with a repetition rate of 83.4 MHz and an average power of 29 W. The OPO, synchronously pumped by the 1.064-μm laser
pulses, consists of a 15-mm-long KTA crystal (cut for type II noncritical phase-matching) in a folded signal resonant linear
resonator. The average powers of the 1.54-μm signal radiation and the 3.47-μm idler radiation are 14.6 W and 6.4 W, respectively.
The total OPO output of 21 W corresponds to an internal efficiency of 75%. The experimental investigations include measurements
of the OPO output power (and its dependence on the pump power, the transmission of the output coupler, and the resonator length)
and of the pulse properties (such as pulse duration and spectral width). The measured results are in good agreement with the
predictions of a numerical analysis based on a split-step Fourier method.
Received: 4 May 1998 相似文献
19.
We report on an idler-resonant femtosecond optical parametrical oscillator(OPO)based on BiB3O6(BiBO)crystal,synchronously pumped by a frequency-doubled,mode-locked Yb:KGW laser at 515 nm.The idler wavelengths of OPO can be tuned from 1100 nm to 1540 nm.At a repetition rate of 75.5 MHz,the OPO generates as much as 400 mW of idler power with 3.1 W of pump power,the corresponding pulse duration is 80 fs,which is 1.04 times of Fourier transform-limited(FTL)pulse duration at 1305 nm.In addition,the OPO exhibits excellent beam quality with M2<1.8 at 1150 nm.To the best of our knowledge,this is the first idler-resonant femtosecond OPO pumped by 515 nm. 相似文献
20.
Two-element-cavity femtosecond Cr(4+):YAG laser operating at a 2.6-GHz repetition rate 总被引:1,自引:0,他引:1
Tomaru T 《Optics letters》2001,26(18):1439-1441
A femtosecond Cr(4+):YAG laser with a simple two-element cavity was built. This laser typically attained a repetition rate of 2.64 GHz with a pulse width of 115 fs at a center wavelength of 1540 nm. Output pulses were characterized by second-harmonic generation frequency-resolved optical gating. Alignment of the two-element cavity for mode-locked operation was easy; moreover, the cavity structure has the potential to produce an even higher repetition rate because one can miniaturize it simply by shortening a gain medium length. 相似文献