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1.
Continuous-wave (CW) simultaneous laser emission on the 0.9-μm 4
F
3/2 → 4
I
9/2 transition and the 4
F
3/2 → 4
I
11/2 transition at 1.06 μm is obtained in Nd-based laser crystals of thin-disk geometry and using a multi-pass pumping scheme.
A Nd:Y 3Al 5O 12 (Nd:YAG) thin disk emitted simultaneous laser radiation at 946 and 1064 nm with 5.1 W output power, and Nd:YVO 4 and Nd:GdVO 4 thin-disk lasers with more than 3 W output power at 0.91 and 1.06 μm were realized. The ratio between the output power at
one of the wavelengths and the total output power could be varied by the laser resonator design. An intracavity frequency-doubled
Nd:YVO 4 thin-disk laser with alternate green at 532 nm and “deep-blue” at 457 nm generation of high average output powers is demonstrated. 相似文献
2.
A thin-disc Nd:GdVO 4 laser in multi-pass pumping scheme was developed. Continuous-wave output power of 13.9 W at 1.06 μm for an absorbed power at 808 nm of 22 W was demonstrated from a 250-μm thick, 0.5-at.% Nd:GdVO 4 in a 4-pass pumping; the slope efficiency in absorbed power was 0.65, or 0.47 in input power. Output performances were also investigated under diode laser pumping at 879 nm, directly into the emitting 4F 3/2 level: maximum power of 3.6 W was obtained at 6.2 W of absorbed power with 0.69 slope efficiency. Compared with pumping at 808 nm, into the highly absorbing 4F 5/2 level, improvements of laser parameter in absorbed power (increase of slope efficiency, decrease of threshold) were obtained, showing the advantages of the pumping into the emitting level. However, the laser performances expressed vs. the incident power were modest owing to the low absorption efficiency at 879 nm. Thus, increased number of passes of the medium would be necessary in order to match the performances in input power obtained under 808-nm pumping. 相似文献
3.
We report a green laser at 541.5 nm generation by intracavity frequency doubling of a continuous wave (cw) laser operation
of a 1083 nm Nd:GdVO 4 laser under 880 nm diode pumping into the emitting level 4
F
3/2. A LiB 3O 5 (LBO) crystal, cut for critical type I phase matching at room temperature is used for second harmonic generation of the laser.
At an incident pump power of 17.8 W, as high as 2.52 W of cw output power at 541.5 nm is achieved. The optical-to-optical
conversion efficiency is up to 14.2%, and the fluctuation of the green output power was better than 3.6% in the given 30 min. 相似文献
4.
Output performances of Nd-vanadate lasers with simultaneous dual-wavelength emission on the 1.06-μm 4 F 3/2 → 4 I 11/2 transition and the 4 F 3/2 → 4 I 13/2 transition at 1.34 μm are discussed. The design uses a linear resonator for emission at 1.06 μm and an L-type folded resonator for the 1.34-μm wavelength, and the ratio between the power of a single wavelength and the total power is adjusted by the choice of the output mirror transmissions. A continuous-wave (CW) Nd:GdVO 4 laser with total output power in the range of 3.9 to 6.8 W and the corresponding ratio of the output power at 1.06 μm to the total output power between 0.26 and 0.97 is realized. It is also shown that in comparison with the pump at 808 nm, the pump directly into the 4 F 3/2 emitting level at 879 nm improves the total output power. Furthermore, a Nd:GdVO 4 laser with simultaneous emission at 1.06 and 1.34 μm and that generates also green light at 0.53 μm by intracavity frequency-doubling with LiB 3O 5 (LBO) nonlinear crystal is demonstrated. 相似文献
5.
A diode-laser-array end-pumped efficient CW Nd:GdVO 4 laser at 1.06 μm has been developed. A low-order-mode output power of 14.3 W was obtained at the maximum available pump power
of 26 W, giving an optical conversion efficiency of 55% and an average slope efficiency of 62%. The laser output beam quality
factor at full pump power was determined to be M 2<1.8. It is also shown that only lightly doped Nd:GdVO 4 crystals are suitable for high-power end-pumped lasers.
Received: 4 May 1999 / Published online: 29 July 1999 相似文献
6.
The influence of the direct pumping into the 4F 3/2 emitting level on the output characteristics of continuous-wave (CW) pumped, passively or actively (acoustooptic, AO) Q-switched Nd lasers is discussed. In case of passive Q-switching by Cr 4+:YAG saturable absorber (SA) crystal, the change of pumping wavelength from 0.81 μm into the highly-absorbing 4F 5/2 level to 0.88 μm into the 4F 3/2 level of Nd does not modify the energy of the Q-switch pulse, but increases the pulse repetition rate and the laser average power for the same absorbed pump power. This is demonstrated with 0.81 and 0.88 μm CW laser diode-pumped Nd:YAG and Nd-vanadate lasers with average output power in the watt-level range at 1.06 μm. The effect is explained by the control of passive Q-switching by the intracavity photon flux that is influenced by the pump wavelength and by the initial transmission of the SA crystal. On the other hand, it is discussed and experimentally proved that due to the possibility to control externally the frequency of switching, in case of the AO Q-switched Nd laser the change of the pump wavelength from 0.81 to 0.88 μm increases the pulse energy for a fixed frequency, leading to a corresponding increase of the average laser power. 相似文献
7.
An 83 W, near-diffraction-limited LD end-pumped Nd:GdVO 4 slab laser with hybrid resonator was presented with the pumping power of 238 W, the slope efficiency and optical-to-optical
conversion efficiency were 39.4 and 34.9%, respectively. At the output power of 70 W, beam quality M 2 factors were 1.2 in stable direction and 1.3 in unstable direction. 相似文献
8.
We report a green laser at 532 nm generation by intracavity frequency doubling of a continuous wave (cw) laser operation of
a 1064 nm Nd:Y 0.5Gd 0.5VO 4 laser under diode pumping into the emitting level 4
F
3/2. A KTiOPO 4 (KTP) crystal, cut for critical type-II phase matching at room temperature is used for second harmonic generation (SHG) of
the laser. At an incident pump power of 17.8 W, as high as 4.21 W of cw output power at 532 nm is achieved. The optical-to-optical
conversion efficiency is up to 23.6%, and the fluctuation of the green output power was better than 2.8% in the given 30 min. 相似文献
9.
To date increasing the output power of Nd:YAG lasers operating on the three-level 4F 3/2→ 4I 9/2 transition has been restricted by detrimental thermal effects in the gain medium. Using a double-clad planar waveguide, an efficient 946 nm laser has been demonstrated that produced 35 W of output power with corresponding slope and optical-to-optical conversion efficiencies of 56% and 50%, respectively. Performance and further power-scaling possibilities are discussed. 相似文献
10.
A high-power continuous-wave (CW) all-solid-state Nd:GdVO 4 laser operating at 1.34 μm is reported here. The laser consists of a low doped level Nd:GdVO 4 crystal double-end-pumped by two high-power fiber-coupled diode lasers and a simple plane-parallel cavity. At an incident pump power of 88.8 W, a maximum CW output of 26.3 W at 1.34 μm is obtained with a slope efficiency of 33.7%. To the best of our knowledge, this is the highest output at 1.34 μm ever generated by diode-end-pumped all-solid-state lasers. 相似文献
11.
The continuous-wave high efficiency laser emission of Nd:YVO 4 at the fundamental wavelength of 914 nm and its 457 nm second harmonic obtained by intracavity frequency doubling with an LBO nonlinear crystal is investigated under pumping by diode laser at 880 nm into emitting level 4F 3/2. 6.5 W at 457 nm with M 2=1.8 was obtained from a 5-mm-thick 0.4 at.% Nd:YVO 4 laser medium and a 15-mm-long LBO nonlinear crystal in a Z-type cavity for 18.6 W absorbed pump power. An optical-to-optical efficiency with respect to the absorbed pump power was 0.35. Comparative results obtained for the pump with diode laser at 808 nm, into the highly-absorbing level 4F 5/2, are given in order to prove the advantages of the 880 nm wavelength pumping. 相似文献
12.
We report a red laser at 671 nm generation by intracavity frequency doubling of a continuous wave (cw) laser operation of
a 1342 nm Nd:Y 0.36Gd 0.64VO 4 laser under diode pumping into the emitting level 4
F
3/2. An GdCa 4O(BO 3) 3 (GdCOB) crystal, cut for critical type I phase matching at room temperature is used for second harmonic generation of the
laser. At an incident pump power of 17.8 W, as high as 1.12 W of cw output power at 671 nm is achieved. The optical-to-optical
conversion efficiency is up to 6.3%, and the fluctuation of the red output power was better than 3.5% in the given 30 min. 相似文献
13.
With a 10-W diode laser to pump Nd:GdVO 4 crystal in a folded cavity, we demonstrated Cr 4+:YAG passively Q-switched Nd:GdVO 4 lasers at 1.06 μm. The maximum average output power of 2.1 W and the highest peak power of 625 W were, respectively, obtained
when the initial transmissions of the Cr 4+:YAG crystals were 90% and 80%.
Received: 8 September 1999 / Revised version: 30 December 1999 / Published online: 8 March 2000 相似文献
14.
High-power and high beam quality continuous-wave (CW) Nd:GdVO 4 lasers operating at 1.34 μm were experimentally demonstrated. The lasers consisted of either one or two crystals, which were both end-pumped by high-power fiber-coupled diode lasers. With one crystal, the maximum CW output power generated was 8.4 W. When two crystals were used, a maximum output power of 15.7 W was achieved with the incident pump power of 76.2 W, showing a slope efficiency of 26.2% and an optical-to-optical efficiency of 20.6%. The beam divergence at an output power of 15 W was measured to be about two times that of the diffraction limit. 相似文献
15.
This paper reports on efficient generation of cw laser radiation at 0.9 and 1.3 μm in different neodymium doped laser hosts.
The thermal, mechanical and optical properties as well as the laser performance of Nd:YAG, Nd:YAlO 3, Nd:YVO 4 and Nd:GdVO 4 are studied in numerical simulations as well as in experimental investigations. For example an output power of more than
4.0 W is generated in Nd:YVO 4 at the 914 nm 4F 3/2→ 4I 9/2 transition using a pump power of 19 W. In Nd:GdVO 4 more than 6.0 W are obtained at the 1342 nm 4F 3/2→ 4I 13/2 laser transition by using a pump power of 19.3 W. The spatial beam quality of both lasers is diffraction limited with an
M 2 value of less than 1.1.
PACS 42.70.Hj; 42.55.Xi; 42.60.Pk 相似文献
16.
In this paper, we report the polarization absorption spectra from 400 to 850 nm, polarization emission spectra from 1050 to 1100 nm and laser properties of an Nd:GdVO 4 crystal. An output power of up to 5.29 W at 1.06 μm has been achieved with a 3×3×3 mm Nd:GdVO 4 crystal sample when it is pumped by a cw laser diode. 相似文献
17.
We propose a novel technique for pumping neodymium vanadate crystal in 4 F 3/2 ?? 4 I 9/2 transition with polarized diode light. With a theoretical model on quasi-three-level neodymium vanadate lasers including excited state absorption and energy transfer upconversion effects, the improvement on the laser performance of polarized pumping is evaluated. A maximum output power of 4.8 W in Nd:GdVO 4 912 nm laser is achieved with the incident pump power of 21.8 W, the maximum output power increases about 85% and the slope efficiency is enhanced to 1.5 times towards the unpolarized pumping under the same condition. This technique is especially suitable for quasi-three-level systems end pumped by high-brightness fiber coupled diode sources associated with short neodymium vanadate crystals. 相似文献
18.
We report continuous-wave (CW) and passively Q-switched Nd :GdVO4 lasers on 4F3/2 → 4I13/2 transition directly pumped by an 880 nm diode laser. A widely investigated Nd :GdVO4 laser at about 1341 nm is operated with a maximum output power of 5.23 W and a slope efficiency of about 30.6%. Using an etalon for wavelength selection, we realize laser emission at about 1344 nm, for the first time to our knowledge, in a Nd :GdVO4 laser, with a maximum output power of 4.19 W and a slope efficiency of 20.1%. Moreover, we achieve simultaneous dual-wavelength lasing at 1341 and 1344 nm with a maximum output power of 2.27 W and a slope efficiency of 13.5%, respectively. Using V3+ :YAG as a saturable absorber, stable Q switching is obtained at about 1341 nm with a maximum average output power of 1.15 W. The pulse width is 52.8 ns at a repetition rate of 279.8 kHz. 相似文献
19.
In this paper, we report a 18.8 W continuous wave and 18.4 W Q-switched diode-pumped cryogenic Tm(5 at %), Ho(0.5 at %):GdVO 4 laser. The pumping source of Tm, Ho:GdVO 4 laser is a fiber-coupled laser diode with fiber core diameter of 0.4 mm, supplying 42 W power at 802.5 nm. For input pump
power of 41.9 W at 802.4 nm, the output power of 18.8 W in CW operation, optical-to-optical conversion efficiency of 45% at
2.05 μm and the average output power of 18.4 W in Q-switched operation, optical-to-optical conversion efficiency of 44% at
2.04 and 2.05 μm have been attained. The emission wavelengths of the Tm(5 at %), Ho(0.5 at %):GdVO 4 laser were firstly compared when it worked in CW mode and Q-switched mode. 相似文献
20.
The continuous-wave high-efficiency laser emission of Nd:GdVO 4 at the second-harmonic of 456 nm obtained by intracavity frequency doubling with an BiB 3O 6(BiBO) nonlinear crystal is investigated under pumping by diode laser at 880 nm into emitting level 4F 3/2. About 3.8 W at 456 nm with M2 = 1.4 was obtained from a 5 mm-thick 0.4 at.% Nd:GdVO 4 laser medium and a 12 mm-long BiBO nonlinear crystal in a Z-type cavity for 13.9 W absorbed pump power. An optical-to-optical efficiency with respect to the absorbed pump power was 0.274. Comparative results obtained for the pump with diode laser at 808 nm, into the highly-absorbing 4F 5/2 level, are given in order to prove the advantages of the 880 nm wavelength pumping. 相似文献
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