Publications by authors named "S Spiekermann"

We developed a visible-red to near-infrared wavelength tunable all-solid-state laser system utilizing an optical parametric generation process in a MgO doped PPLN crystal pumped at 532 nm by an amplified and frequency doubled picosecond passively Q-switched Nd:YVO microchip laser. A broad bandwidth, tuneable over 300 nm between 710 nm to 1015 nm, is accessible. Depending on the green pump light pulse energy, pulses with durations down to 69 ps as well as pulses with energies above 2 µJ were achieved with kHz repetition rates.

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We present a monolithic integrated passively Q-switched sub-150 ps microchip laser at 1064 nm with a wedged Nd:YVO crystal operating up to a repetition rate of 1 MHz. The wedge enables to change the cavity length by a small amount to fine tune the spectral cavity mode position over the full gain bandwidth of Nd:YVO and hence to optimize the output power. This additional degree of freedom may be a suitable approach to increase the wafer scale mass production yield or also to simplify frequency tuning of CW single-frequency microchip lasers.

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Efficient continuous-wave and passively Q-switched diode-laser-pumped Nd:YAG lasers at 946 nm are reported together with results on highly efficient frequency doubling. Periodically poled KTiOPO(4) was employed as the nonlinear material because of its high nonlinearity and its resistance to photorefractive damage. In the blue spectral region we measured 76 mW in continuous wave and 285 mW in the Q-switched mode.

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Background: Flow-mediated dilation (FMD) of human conduit arteries is, in part, related to shear stress-induced release of endothelium-derived nitric oxide (NO). However, NO synthase inhibitors do not completely abolish this FMD-response. Recently, a cytochrome P450 (CYP) epoxygenase of the 2C family was linked to NO- and prostacyclin-independent relaxation of conduit arteries.

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