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We report highest power conductive-cooled Yb:YAG active-mirror amplifier (CcAMA) delivering 1 kW average power in 10 J, 100 Hz.

Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is the future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could be produced during the inflationary period right after the birth of the universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in the heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry-Perot Michelson interferometers with an arm length of 1,000 km. Three clusters of DECIGO will be placed far from each other, and the fourth cluster will be placed in the same position as one of the three clusters to obtain the correlation signals for the detection of the primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder of DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand the multi-messenger astronomy., Comment: 10 pages, 3 figures

Ytterbium doped laser materials have been intensely investigated for developing high power laser-diode pumped solid-state lasers around 1 μm (Krupke 2000). Yb:YAG as crystals and polycrystalline ceramics are one of the dominant laser gain media used for solid-state lasers (Lacovara et al., 1991; Brauch et al., 1995; Bruesselbach et al., 1997; Taira et al., 1997; Dong et al., 2006) owing to the excellent optical, thermal, chemical and mechanical properties (Bogomolova et al., 1976). Owing to the small radius difference between yttrium ions and ytterbium ions (Dobrzycki et al., 2004), Yb:YAG single-crystal doped with different Yb concentrations can be grown by different crystal growth methods and efficient laser performance has been achieved (Brauch et al., 1995; Patel et al., 2001; Dong et al., 2006). Transparent laser ceramics (Lu et al., 2000; Lu et al., 2001; Lu et al., 2002; Takaichi et al., 2003; Dong et al., 2006) fabricated by the vacuum sintering technique and nanocrystalline technology (Yanagitani et al., 1998) have been proven to be potential replacements for counterpart single crystals because they have several remarkable advantages compared with single-crystal laser materials, such as high concentration and easy fabrication of large-size ceramics samples, multilayer and multifunctional ceramics laser materials (Yagi et al., 2006; Dong et al., 2007). Efficient and high power laser operation in Nd

A stable operation of 1.1 J/100 Hz 10 ns laser pulses were achieved from a single cryogenically cooled Yb:YAG rod amplifier with ink-cladding. The efficiency and gain coefficient were 44% and 383, respectively.

iNaturalist is a social network of people who record and share observations of biodiversity. For several years, iNaturalist has been employing computer vision models trained on iNaturalist data to provide automated species identification assistance to iNaturalist participants. This presentation offers an overview of how we are using this technology, the data and tools we used to create it, challenges we have faced in its development, and ways we might apply it in the future.

We measured the chiral relaxation of photoexcited Fenchone at the Carbon K-edge. Our results demonstrate that ultrafast chiral dynamics can be probed using core level spectroscopy with circularly polarized free-electron laser pulses.

We have directly generated two kinds of vector polarized beam pulses from an end pumped rotating Nd:YAG disk laser design acousto-optic Q-switch pulse modulation. About 20 ns pulse width with peak power 29 kW and stable pulse vector polarized beams are achieved at the continuous absorbed pump power. The laser crystal rotary effectively alleviates thermal effect that affects the power scaling with high beam quality. The output state is controlled by an intra-cavity polarization selector birefringent crystal. The polarization degrees of the azimuthally and radially polarized beams are 98.6% and 98.2%, respectively. The study suggests that this new method would constitute a laser light source for producing power and single pulse energy scaling, short pulse width, and high-purity structured vector beams and serve this function.

We demonstrated an LG01-mode vortex Ti:Sapphire laser by utilizing an intracavity spot defect for spatial filtering. At the 140-μm diameter of spot defect, the power of vortex laser output reached 135 mW, and the slope efficiency of laser was 17.7%. The effects of the sizes of spot defects on the transverse laser modes and laser powers were also discussed.

We demonstrated the generation of an azimuthally and radially polarized laser beam in a Nd:YAG laser in which a birefringent yttrium vanadate (c-cut YVO4) crystal was used as the intra-cavity polarization discriminator. AP and RP with respective output 2.4W (o-o efficiency of 35.4%, M2 = 2.3) and 2.52W (o-o efficiency of 37.2%, M2 = 2.4) were generated at absorbed pump power 6.78W. We discuss a simple method for converting between azimuthal and radial polarizations by only regulating input pump power and mechanism of mode selection in the laser. This vector laser will facilitate many applications.

A azimuthally polarized laser pulse was produced from a passively Q-switched rotating Nd:YAG disk laser with a Cr4+:YAG crystal as the saturable absorber and a uniaxial YVO4 crystal as the polarization selection. The averaged laser power reached 5.04 W with a slope efficiency of 40%. The laser pulse had a maximum peak power of 4.3 kW, minimum pulse duration of 31.07 ns, and a 37.3 kHz repetition rate at absorbed pump power 15.93 W. The polarization degree of the azimuthally polarized beam was measured to be about 97.3%. Such an azimuthally polarized laser pulse is important to numerous applications.

Autoionizing hole states with electron configuration nsnp5 mp are studied in Ar+ and Kr+. Total and partial photoionization cross sections, photoelectron spectra and photoelectron angular distributions in the region of the resonances are obtained theoretically in extensive R-matrix calculations. The states of Ar+ are observed by means of excitation by a free-electron laser operating in the vacuum- and extreme-ultraviolet wavelength regime combined with angle-resolved photoelectron spectroscopy. Fine tuning of the photon energy allows scanning of the resonances and the observation of the shape of the partial cross section ratio, as well as the asymmetry parameter of the angular distribution of the photoelectrons. The calculations are in good agreement with the experimental data.

A rotating neodymium-doped yttrium aluminum garnet (Nd:YAG) disk laser resonator for efficiently generating vector beams with azimuthal and radial polarization is demonstrated. In the study, the laser crystal rotary for thermal alleviation and polarization discrimination uses c-cut ytterbium vanadate (YVO4). The laser output could be switched between azimuthal and radial polarizations by simply adjusting the cavity length. The laser power reached 4.38 W and 4.64 W for azimuthally and radially polarized beams at the slope efficiencies of 45.3% and 48.5%, respectively. Our study proved that an efficient, high-power vector rotary disk laser would be realistic.

The concept of a high-power thin-rod Yb:YAG laser amplifier with high-brightness diode pumping was proposed. The principle of the amplifier parameter variation aimed at achieving an efficient signal gain at different power levels was developed. Three versions of thin-rod gain modules were implemented, where small and strong signal gains were studied experimentally. The ultrafast laser system with high average power (28 W) and high pulse energy (2.5 mJ) was created on the basis of the unique thin-rod gain modules.

In recent years, Yb3+ doped calcium fluoride (Yb:CaF2) has attracted great attention as a gain media for ultrashort pulse laser oscillator and amplifier. Yb:CaF2 has many advantages suitable for mode locked laser e.g. very broad and smooth fluorescence spectrum shape, relatively high thermal conductivity, and long fluorescence lifetime [1]. Especially, its fluorescence spectrum bandwidth of about 70 nm is much broader than other typical broad gain media and comparable with Yb:CALGO. Such broad spectrum bandwidth helps significant pulse shortening of ultrashort pulse laser. In addition, the relatively higher thermal conductivity of 9.7 W/mK (non-dope) is suitable for high power operation. Thanks to those advantages, Yb:CaF2 has already shown very good results as mode-locked laser, ultrashort pulse amplifier and thin disk laser. But all of those reports were based on Yb: CaF2 single crystals and Yb: CaF2 ceramic is under development. Transparent ceramics have many advantages for high power laser gain media. Hence recently fabrication of rare-earth doped CaF2 ceramics have been tried extensively [2-4]. In this paper, we report the first mode-locked operation using Yb3+-doped CaF2 ceramic based material, Yb3+-doped CaF2-LaF3 ceramic as a gain media. Our ceramic was fablicated by HIP base sintering method and contained a few at.% of LaF3 as a co-dopant to increase the transparency and mitigate divalent ytterbium ions (Yb2+) formation.

Highly transparent ceramic is an attractive gain medium for high-power lasers due to its high fracture toughness, homogeneity, and size scalability. Here we report the first Yb

DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) is the planned Japanese space gravitational wave antenna, aiming to detect gravitational waves from astrophysically and cosmologically significant sources mainly between 0.1 Hz and 10 Hz and thus to open a new window for gravitational wave astronomy and for the universe. DECIGO will consists of three drag-free spacecraft arranged in an equilateral triangle with 1000 km arm lengths whose relative displacements are measured by a differential Fabry-Perot interferometer, and four units of triangular Fabry-Perot interferometers are arranged on heliocentric orbit around the sun. DECIGO is vary ambitious mission, we plan to launch DECIGO in era of 2030s after precursor satellite mission, B-DECIGO. B-DECIGO is essentially smaller version of DECIGO: B-DECIGO consists of three spacecraft arranged in an triangle with 100 km arm lengths orbiting 2000 km above the surface of the earth. It is hoped that the launch date will be late 2020s for the present..

We report on the results of low-temperature stimulated Raman scattering (SRS)-spectroscopy of tetragonal GdVO4 single crystals. Measurements at T ≈ 9 K and picosecond excitation in the visible and near-infrared range revealed new manifestations of χ(3)-nonlinear photon–phonon interactions. Besides many-phonon Stokes and anti-Stokes octave spanning SRS generation we discovered a new fundamental χ(3)-active phonon mode of the crystal. Furthermore, we received data on combined SRS-active vibrational modes. The lower limits of the steady-state Raman gain coefficients for first Stokes generation have been estimated together with the temperature dependence of these values in the range from T ≈ 9 and 273 K. A short review of SRS-promoting vibrational modes and manifestations of χ(3)-nonlinear interactions of all known SRS-active tetragonal rare-earth REVO4 vanadates is given as well.

Transparent Nd3+-doped Ba(Zr,Mg,Ta)O3 ceramics with disordered-type crystals were fabricated by adjusting the Ba(Zr,Mg,Ta)O3 composition in order to substitute Nd dopants at different crystal sites. The XRD and XRFS analyses show that the substitution site of Nd ions changed as expected. In samples excited by a 805 nm laser diode, the shape of the fluorescence spectrum in the 4F3/2 → 4I11/2 transition depends on the Ba(Zr,Mg,Ta)O3 composition, and a maximum full width half maximum of 30.5 nm was obtained. In addition, the fluorescence efficiency also improved by adjusting the Ba(Zr,Mg,Ta)O3 composition.

DECi-hertz Interferometer Gravitational-wave Observatory (DECIGO) is a future Japanese space gravitational-wave antenna. The most important objective of DECIGO, among various sciences to be aimed at, is to detect gravitational waves coming from the inflation of the universe. DECIGO consists of four clusters of spacecraft, and each cluster consists of three spacecraft with three Fabry–Perot Michelson interferometers. As a pathfinder mission of DECIGO, B-DECIGO will be launched, hopefully in the 2020s, to demonstrate technologies necessary for DECIGO as well as to lead to fruitful multimessenger astronomy. B-DECIGO is a small-scale or simpler version of DECIGO with the sensitivity slightly worse than that of DECIGO, yet good enough to provide frequent detection of gravitational waves., ファイル公開：2020/09/01

Parasitic thermal effects (thermal depolarization and thermal lens) of three Konoshima Chemical Co. laser-ceramics samples Yb3+:Lu2O3(CYb≈1.8%), Yb3+:Y2O3(CYb≈1.8%), and Yb3+:Sc2O3(CYb≈2.5%) were measured in experiment at different pump power. The obtained results were used to calculate a number of thermo-optical constants, which showed that sesquioxide ceramics are significantly superior to the widely used yttrium aluminum garnet Yb3+: Y3Al5O12(CYb≈10%). (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A study on Laguerre-Gaussian (LG) modes selection in cw and pulsed Nd:YAG or Yb:YAG ceramic lasers pumped by diodes or an external laser source was carried out. Methods of scalar and vector LG modes selection from low to high orders, involving shaping of the pump profile, usage of intra-cavity lenses, uniaxial crystals and polarization selective mirrors, are considered. CCD camera images of beam profiles of hollow scalar LGpm modes (p -radial, m -azimuth indices) of record high-orders and Bessel-like multi-ring modes with highly directional propagation properties are presented. CW and pulsed ceramic lasers with radially or azimuthally polarized LG vector modes of low and high orders are also demonstrated. Applications of the developed laser schemes and LG beams are discussed. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The excitation of vector modes in a few-mode fiber by varying the polarization states of Gaussian incident beam at different off-axis conditions was investigated. As a result, the linearly polarized incidence orientated at four different off-axis conditions excited radially polarized TM 01 mode, azimuthally polarized TE 01 mode, hybrid polarized HE 21 mode, or linearly polarized two-lobe mode separately. Further, the left/right circularly polarized incidence excited linearly polarized two-lobe mode and the excited mode was interpreted as the combination of HE 21 and TM 01 (/TE 01 ) modes with equal amplitude. The left/right elliptically polarized incidence excited the two-lobe mode with the crescent conglutination between each pair of lobes and the excited mode was interpreted as the combination of HE 21 mode and TM 01 (or TE 01 ) mode with unequal amplitude.

We report three new laser materials. Nd 3+ -doped Ba(Zr, Mg, Ta)O 3 ceramic indicates a broadband luminescence spectrum due to its disordered structure. By optimizing the manufacturing process and laser configuration, high output power and high slope efficiency operation was obtained. Nd 3+ (Na + ):Ca 2 MgSi 2 O 7 shows another type of spectral broadening caused by its structural modulation. In the input–output property, an anomalous behavior due to phase transition was observed. Yb 3+ :Lu 3 Al 5 O 12 is one of the important laser materials for thin-disk laser because it indicates mild reduction of the thermal conductivity as an increase of concentration. The highly efficient CW laser operation is reported.

We present several previously unexplored χ(3)-nonlinear laser effects under picosecond excitation in LuVO4 and YbVO4. Among them high-order Stokes and anti-Stokes generation related to discovered SRS-promoting vibration modes, with the manifestations of cross-cascaded χ(3) ↔ χ(3) lasing processes involving new SRS-active phonons. All recorded spectral components of many-phonon χ(3)-nonlinear generation were identified and attributed to the vibrations of the (VO4)3- structural units of the studied vanadates. On the 50th anniversary of the discovery of stimulated Raman scattering

Multi-wavelength continuous-wave (CW) Raman lasers in a laser diode pumped Yb:YAG/Nd

A 30.8-W output power at 355 nm is generated in CsLiB 6 O 10 crystal using a hybrid picosecond MOPA seeded by a gain-switched LD. The conversion efficiency from the fundamental source to the third harmonic reaches 48.1%.

We prepared transparent Yb:CaF 2 -LaF 3 ceramics with different combinations of doping concentrations of Yb3+ and La3+ and obtained CW laser operation with maximum output of 3.97 W. The maximum slope efficiency was as high as 73.1%.

We found that tetragonal Gd0.5Lu0.5VO4—known as host-crystal for Ln3+-lasants—is an attractive optical material for Raman laser converters. We discovered and investigated its almost sesqui-octave Stokes and anti-Stokes lasing comb resulting from four SRS-promoting vibration modes in combination with cascaded and cross-cascaded many-phonon χ(3)-nonlinear interactions. Furthermore, estimations of the steady-state Raman gain coefficient have been performed.

Participatory adaptive management is widely promoted as the new paradigm in public lands management. It is grounded in two underlying principles - that management experiments and diverse sources of information should be used to continually refine management in complex ecological systems, and that the public must be included throughout the adaptive management process. Access to scientific results and exchange of information is at the core of both of these principles. The recent proliferation of Internet communities and web-based participation tools raises the question of how the Internet might help facilitate information exchange in participatory adaptive management. Using a case study approach, the role of web technologies in facilitating the flow of transparent and useful information was examined in a participatory adaptive management project focused on Forest Service vegetation management treatments in California's Sierra Nevada. Three evaluation methods were used: analysis of web usage and content, a survey of active participants, and a review of comments posted to the project website. Results suggest that the web played an important role throughout the adaptive management cycle by supporting communication through disseminating information to the public and increasing the transparency of the scientific process. The web played a small, but important role in public consultation, by providing a forum for targeted questions and feedback from the public. Internet technology did not actively support the two-way flow of information necessary for mutual learning. Web technology complements face-to-face interactions and public meetings, rather than replacing them.

Over the last twenty years, diode pumping of solid-state lasers has opened new prospects for the mode control and formation of Laguerre-Gaussian (LG) beams, enabling a large variety of applications. Experiments on scalar and vector LG modes selection in Nd3+- and Yb3+-doped ceramics and crystal lasers carried out at the Institute for Laser Science, Tokyo are reviewed. Selection of LG modes from low to high orders using intra-cavity elements, polarization-selective mirrors, or shaping the pump beam profile, is considered. Illustrations of record-high-order LG hollow modes, multiring modes with highly directional propagation properties, characteristics of cw and pulsed lasers with radially or azimuthally polarized beams of high polarization purity are presented. General solutions of the wave equation for the axi-symmetric electric field, which describe LG beams of various profiles, are proposed for data analysis. In parallel, a short review on LG modes selection studies carried out at other laboratories is given.

Highly transparent Tm:Ho:YAG transparent ceramics were prepared using advanced ceramic technology and their spectroscopic properties were studied for infrared laser applications. Following the Judd-Ofelt procedure several spectroscopic properties such as the radiative transition probability (Arad), radiative decay time (� rad) and fluorescence branching ratio (� ) are quantitatively obtained from the absorption spectrum. The absorption and emission cross sections corresponding to the 5I7 → 5 I8 transition of Ho 3+ at 2.1 � m have been evaluated following Mc Cumber theory and found that the obtained emission spectrum very well correlates to the simulated emission spectral data. The optical gain spectrum spread from 1800 nm to 2150 nm with a spectral width of over 107 nm and maximum gain coefficient of 0.44 cm −1 . Thus it is expected that the Tm 3+ :Ho 3+ :YAG ceramics

Continuous-wave and passively Q-switched microchip laser performance of Yb:YAG ceramics and single-crystals was investigated. Highly efficient continuous-wave Yb:YAG laser performance was observed at 1030 nm and 1049 nm for both Yb:YAG ceramics and crystals with different transmissions of output couplers. The laser performance of Yb:YAG ceramic is comparable to that of Yb:YAG single crystal. Meanwhile, the laser performance of laser-diode pumped Yb:YAG/Cr4+:YAG all-ceramics- and all-crystals-combination passively Q-switched microchip lasers were investigated. Sub-nanosecond laser pulses with peak power over 150 kW were obtained with different Yb:YAG/Cr4+:YAG combinations. Linearly polarized laser was observed in Yb:YAG/Cr4+:YAG all-crystals combination and circular polarized laser was obtained in Yb:YAG/Cr4+:YAG all-ceramics combination. The best laser performance was obtained with Yb:YAG/Cr4+:YAG all-crystals combination.

In this paper, we demonstrated an actively Q-switched, radially polarized, and laser-diode end-pumped Nd:YAG laser with an acousto-optic modulator as the Q switch and a photonic crystal grating as the output coupler. The laser generated pulses of 26.4–67.2 ns duration, and the repetition rate can be continuously adjusted from 500 Hz to 9.238 kHz with peak power up to 7.75 kW. Such a radially polarized pulse would facilitate numerous applications.

Multiple Stokes and anti-Stokes χ(3)-nonlinear generation in the tetragonal crystal of CaYAlO4 was observed at 300 K and ≈ 9 K under picosecond excitation in the visible spectral range. All the recorded Raman induced laser lines were identified and attributed to the SRS-promoting vibration mode of octahedral [AlO6]-9 units of the crystal.

The laser characteristics of laser-diode end-pumped Yb:YAG/Cr4+:YAG composite ceramics microchip passively Q-switched lasers were studied by solving the coupled rate equations numerically taking into account the reabsorption of Yb:YAG ceramics at laser wavelength. Effects of the reflectivity of the output coupler, the concentrations and thickness of the saturable absorbers, and pump beam area on the laser performance were investigated analytically. The simulation results of the Yb:YAG/Cr4+:YAG composite ceramics passively Q-switched microchip lasers were in good agreement with the experimental data. Better laser performance (high peak power, short pulse width and good optical-to-optical efficiency) of the composite Yb:YAG/Cr4+:YAG ceramics passively Q-switched laser can be obtained by using a thin Cr4+:YAG ceramic with high concentration, suitable reflectivity of the output coupler and proper pump beam diameter under high pump power intensity according to our simulations.

Institute of Crystallography of the Russian Academy of Sciences; Institute of Optics and Atomic Physics of the Technical University of Berlin; Institute of Crystallography of the University of Cologne; Institute for Laser Science of the Tokyo University o

Program for New Century Excellent Talents in University (NCET) [NCET-09-0669]; Fundamental Research Funds for the Central Universities [2010121058]; Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (SRF f

The spectroscopic and stimulated-emission (4F3/2→4I11/2) properties of the novel melilite-type laser crystal Ca2MgSi2O7:Nd3+(Na+) were studied in a temperature range that covers its incommensurate–commensurate (IC↔N) phase transition. The phase transition temperatures of both undoped Ca2MgSi2O7 and the doped crystal were ascertained at 346.6 K (undoped) and 341.3 K (doped) by means of differential scanning calorimetry (DSC). The temperature-dependent spectroscopic and laser experiments showed a significant decrease in CW output power and a strong distortion of the generated lasing beam in the region of the phase transition. The observed crystal field disorder of Nd3+ lasants in Ca2MgSi2O7:Nd3+(Na+) is dominantly due to occupation of the position of Ca2+ by cations of different valency, while the influence of incommensurability is of minor importance.

In this paper are present results of the first investigation of stimulated Raman scattering (SRS) in the ``garnet'' Lu3Al5O12 crystalline ceramics, which is promising host-material for activator lasants. With picoseconds laser excitation at 0.53207 μm wavelength was observed and analyzed high-order Stokes and anti-Stokes generation related to two χ(3)-promoting vibration modes (≈ 792 and ≈ 375 cm-1) of this novel SRS-active oxide material. A brief review of the pioneering papers on lasers based on Lu3Al5O12:Ln3+ single crystals and known SRS-active crystalline ``garnet'' materials is given in tabular form as well.

This letter reports the generation of watt-level radially polarized light from an LD end-pumped Nd:YAG laser by utilizing a photonic crystal grating as the polarization-selective output coupler. The Nd:YAG crystal is bonded with two un-doped YAG crystal end caps, which is used to weaken the thermal lens effect and thus enhance the extraction of stored energy in bulk gain material. The radially polarized output from this laser reached 1.29-W laser power, 46.5% slope efficiency and a polarization purity of 97.9%.

A short-focus glass lens with strong spherical aberration was used for mode selection in the cw LD-end-pumped Yb:YAG ceramic laser. Sequence of low to very high order Laguerre–Gaussian (LGpl) modes with different combinations of radial, p and azimuthal, l indices (p ⩽ 10, l ⩽ 28), with output beam diameters 2–13 mm and power up to 30 mW was obtained. Peaked and hollow multi-ring beams with near-diffraction free propagation of the central minimum or maximum over 40 m distance from the laser resonator were observed. Mechanisms of mode selection and possible applications of the proposed laser scheme are considered.

Yb-doped fiber laser operating at the long-wavelength edge (1150–1200 nm) of the broad gain spectrum has been investigated for yellow-orange sources. Power scaling in this region has been recently achieved by Yb-doped solid-core photonic bandgap fibers, in which the Yb gain profile is engineered by the sharp-cut, bandpass distributed filtering and therefore amplified spontaneous emission in the high-gain region (1030–1100 nm) is strictly inhibited. We have recently demonstrated amplification with as high as 167 W output power and 61% slope efficiency at 1178 nm. The novel gain profiling technique by photonic bandgap fibers can be extended to other rare-earth doped fibers.

Using single- and dual-wavelength coherent collinear picosecond pumping we observed in semi-organic heterodesmic orthorhombic [C(NH 2 ) 3 ] 2 Zr[N(CH 2 COO) 3 ] 2 ·H 2 O manifestations of several new χ (3) - and χ (2) -nonlinear optical effects, among them self-frequency doubling, "Cherenkov"-type second harmonic generation (SHG), cascaded self-frequency tripling and self-sum-frequency generation, as well as more than two-octave Stokes and anti-Stokes generation under one-micron excitation. All newly recorded nonlinear optical frequency components were identified and attributed to stimulated Raman scattering (SRS) promoting modes of the crystal. All three tensor components of the second order nonlinear optical susceptibility tensor (SHG tensor) were determined at the wavelength 1.064 μm using the Maker fringe technique. The maximal value of the SHG tensor is 0.6 pm V ―1 . SHG phase matching directions of type-I/II and effective nonlinear susceptibilities are given for 0.7―1.4 μm fundamental wavelengths.