We report on efficient broadband sum-frequency generation, converting a 140 THz near-infrared bandwidth to the visible regime with photon conversion efficiency greater than 90%. Using a 20-mm-long aperiodically adiabatively poled KTP crystal, the spectral range 660-990 nm was converted to 405-500 nm using a strong pump wave at 1030 nm. The photon conversion efficiency was confirmed to be 92±0.5...

Ceramic YAG/Yb:YAG/YAG planar waveguide lasers were realized on continuous-wave and mode-locked operations. The straight waveguide, fabricated by non-aqueous tape casting and solid state reactive sintering, enabled highly efficient diode-pumped waveguide continuous-wave laser with the slope efficiency of 66% and average output power of more than 3 W. The influence of the waveguide structure on ...

Multi-Watt efficient compact green laser sources are required for a number of applications e.g. within biophotonics, laser pumping and laser displays. We present generation of 3.5 W of diffraction-limited green light at 515 nm by second harmonic generation (SHG) of a tapered diode laser, itself yielding more than 9 W at 1030 nm. SHG is performed in single pass through a cascade of two nonlinear...

We describe the design and performance of a high-repetition-rate single-frequency passively Q-switched Yb:YAG microlaser operating near 1030 nm. By using short cavity length, an intracavity Brewster polarizer, and an etalon output coupler, we are able to produce ~1-ns-long single-frequency pulses at repetition rates up to 19 kHz without shot-to-shot mode hopping. The laser’s output spatial mode...

We have examined if sevoflurane anaesthesia per se modified the number of circulating leucocytes in humans. Fifty-nine patients undergoing elective surgery were anaesthetized with sevoflurane in oxygen. The inhaled concentration was increased gradually to 5% and maintained for 20 min. Arterial blood samples were obtained before induction of anaesthesia and at 20 min. While the total number of l...

In this paper, a new algorithm called wavelet correlogram-CCV (W3C) for contentbased image indexing and retrieval is presented. W3C is an extension of wavelet correlogram that utilizes color coherence vectors (CCV) to consider texture information in addition to the shape for gray-level images. Additionally, a new distance measure that is optimized by genetic algorithms is proposed. The retrieva...

We show that if a Barker sequence of length n > 13 exists, then either n = 189 260 468 001 034 441 522 766 781 604, or n > 2 · 1030. This improves the lower bound on the length of a long Barker sequence by a factor of more than 107. We also show that all but fewer than 1600 integers n ≤ 4 ·1026 can be eliminated as the order of a circulant Hadamard matrix. These results are obtained by completi...

Positively chirped femtosecond pulses at 1030 nm are wavelength-converted using spontaneous and stimulated Raman scattering in a potassium gadolinium tungstate crystal inserted inside multipass cell. Recirculation the cell material allows both high conversion efficiency good spatial beam quality for generated Stokes beams. The converted can be compressed to sub-picosecond duration. Multipass ce...

Fine zinc oxide particles were electrophoretically deposited  on alumino-ferro-chrome substrates. The deposition was carried out in a cylindrical ZnO/acetone electrophoresis cell. The deposits were dried and sintered at 1030³C in air. The process resulted a porous polycrystalline ZnO cladding over the alloy core. Comb shaped silver electrodes were formed and fired at 350³C. The variation of dev...

A high-efficiency fiber laser at 1018 nm using homemade Yb-doped phosphosilicate fiber is demonstrated. The fiber shows blueshifted emission spectrum compared to Yb-doped aluminosilicate fiber, and is considered favorable for the short wavelength Yb-doped fiber laser. With a 7 m gain fiber, up to 22.8 W output at 1018 nm is achieved with an optical efficiency of 53%. The amplified spontaneous e...