Hidetsugu Yoshida

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As the first demonstration of Faraday effect in a TGG ceramics, its Verdet constant at 1053 nm is evaluated to be 36.4 rad/Tm at room temperature which is same as that of the single crystal. In addition, the temperature dependence of Verdet constant is obtained experimentally. At liquid helium temperature, it is 87 times greater than that at room(More)
We have developed a high-power laser system based on optical parametric chirped-pulse amplification in a beta-BaB2O4 crystal. The system provides gain of 10(8), a conversion efficiency of approximately 23%, an output energy of -65 mJ, and good amplified beam quality. The prepulse ratio has been measured to be 1.5 x 10(-8) or less. The spectral width was as(More)
We report a high-average-power laser-diode-pumped Nd:YAG master oscillator power amplifier system that has a minimum number of elements in the single multipass zigzag-slab amplifier stage and is used to pump a high-peak-power and high-average-power Ti:sapphire laser system. This phase-conjugated system produces an average power of 362 W at 1 kHz in a 30-ns(More)
The optical properties, Faraday effect and Verdet constant of ceramic terbium gallium garnet (TGG) have been measured at 1064 nm, and were found to be similar to those of single crystal TGG at room temperature. Observed optical characteristics, laser induced bulk-damage threshold and optical scattering properties of ceramic TGG were compared with those of(More)
We report a high-average-power and high-pulse-energy diode-pumped Nd:glass laser amplifier system consisting of two thermally-edge-controlled zigzag slab amplifiers and a stimulated Brillouin scattering mirror. This phase-conjugated system produces an average power of 213 W at 10 Hz in a 8.9 ns pulse (2.4 GW peak power) with an optical-to-optical conversion(More)
Commercial catches of barfin flounder Verasper moseri, an important target flatfish for stock enhancement programs in northern Japan, have recovered remarkably since the large-scale release of seedlings from Hokkaido in 2006. However, their reproductive ecology remains unclear. Our study of 2008–2012 investigated seasonal changes in the maturity of stocked(More)
An ultraintense laser injected a 10 J of power at 1.053 microm in 0.5 ps into a glass capillary of 1 cm long and 60 microm in diameter and accelerated plasma electrons to 100 MeV. One- and two-dimensional particle codes describe wakefields with 10 GV/m gradient excited behind the laser pulse, which are guided by a plasma density channel far beyond the(More)
We have achieved a high compression ratio by stimulated Brillouin scattering (SBS) consisting of two long cells. A 13-ns Nd:YAG laser pulse was temporally compressed to about 160-ps phase-conjugated pulse in heavy fluorocarbon FC-40 liquid at a 1064 nm wavelength. The maximum reflectivity of SBS process was over 80 % without an optical damage. The(More)
We describe a sub-nanosecond pulse laser system that delivers high-average-power green and ultraviolet (UV) light. This system includes a front end, two modules each of which has four photonic crystal fiber main amplifiers, two sets of coherent beam combiners with efficiencies of 83 and 90%, and two sets of harmonic converters. A single beam was ultimately(More)