6.3 Watts of single frequency output has been generated by single-pass frequency-doubling of a fiber-laser-pumped CW
OPO. 40% efficient frequency doubling was demonstrated by focusing 15.8 Watts of 1560nm input into an 80mm length
MgO:PPLN crystal. The single frequency 1560nm input was generated as the resonant signal wavelength in a CW OPO
based on MgO:PPLN. The OPO was pumped by a 30 Watt Ytterbium-doped fiber laser operating at 1064nm, with a
spectral bandwidth of ~0.6nm.
We have demonstrated 23 Watts total output power from a CW OPO. We believe this to be the highest total power
output yet demonstrated from this class of device. The OPO was based on MgO-doped PPLN and was pumped by a 30
Watt fiber laser. The external efficiency was 77 % and the corresponding pump depletion was 83%. Output of 16.8
Watts at 1.5 microns and 6.2 Watts at 3.6 microns was demonstrated. We have also demonstrated simultaneous output of
10 Watts at 1.96 microns and 8 Watts at 2.34 microns in the same device.
We report on the first successful generalized Mueller-matrix ellipsometry measurements in the THz-frequency domain using the high-brilliance THz synchrotron radiation source IRIS at the electron storage ring BESSY, Germany. Generalized Ellipsometry, which is known as a powerful tool for measurement of optical constants including anisotropy and which was previously used in the FIR to VUV spectral range, is now employed for the first time to investigate condensed matter samples in the frequency range from 0.9 to 8 THz (30 to 650 cm<sup>-1</sup>). Exemplarily, results obtained from bound and unbound charge-carrier investigations in low-dimensional semi- and superconducting systems are presented. Future applications of this technique for investigation of charge-carrier dynamics in magnetic fields are envisioned.