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project, see www.ki-sigs.de, which is funded by the German Federal Ministry for Economic Affairs and Climate Action (BMWK) and involves several universities, research institutions and private companies in northern Germany. Researchers YP, SB and LP are employed through funding from the KI-SIGS project. Neither the funding agency nor the involved private companies have had any influence on the planning and design of this survey, the writing of the manuscript, or the publication process. This research was conducted while EP was at Universität zu Lübeck.

We present a magnetic actuation scheme combined with a piezoresistive MOS-transistor sensing technique for CMOS-integrated resonators. It was developed for a cantilever resonator with on-chip amplifier, but is broadly applicable. The high efficiency of electromagnetic actuation significantly reduces the required operation power and allows for the use in portable devices. By use of stress-sensitive PMOS-transistors as active loads, the size of the piezoresistive Wheatstone bridge is significantly reduced. Thirdly, the post-processing sequence of the cantilever resonator has been optimized, so that only one photolithography step is necessary to release the whole mechanical structure. This facilitates the fabrication, increases yield and, thus, reduces fabrication cost.

Planar waveguides in nonlinear optical crystals of Sn(2)P(2)S(6) have been produced by He+ ion implantation. The effective indices of the waveguide have been determined and refractive index profiles have been evaluated for the indices along all three principal axes of the optical indicatrix. The depth of the induced optical barrier is n1 = -0.07, n2 = -0.07 and n3 = -0.09 at lambda = 0.633 microm for a fluence Phi = 0.5x10(15)ions/cm(2). Propagation losses for hybrid-n(1) modes are alpha approximately 10dB/cm.

Recent studies demonstrate therapeutic benefits in retinal laser therapy even for non-visible effects of the irradiation. However, in practice, ophthalmologists often rely on the visual inspection of irradiation sites to manually set the laser power for subsequent ones. Since absorption properties vary strongly between sites, this procedure can lead to under- or over-treatment. To achieve safe automatic retinal laser therapy, this article proposes a robust control scheme based on photoacoustic feedback of the retinal temperature increase. The control scheme is further extended to adapt to real-time parameter estimates and associated bounds on the uncertainty of each irradiation site. Both approaches are successfully validated in ex vivo experiments on pigs’ eyes, achieving consistent irradiation durations of 55 ms despite the uncertainty in absorption properties.

We report on the electro-optic and nonlinear optical properties of waveguides produced by low fluence (Phi = 1.25x10(14) ions/cm(2)) H+ ion implantation in the organic nonlinear optic crystal 4-N,N-dimethylamino-4'-N'-methyl-stilbazolium tosylate (DAST). The profile of the nonlinear optical susceptibility has been determined by measuring the reflected second-harmonic generation efficiency from a wedged-polished sample at a fundamental wavelength of lambda(omega) = 1176nm. In the waveguide core region the nonlinear optical susceptibility is shown to be preserved to more than 90% of its bulk value. A model which relates the molecular changes to the measured macroscopic alteration of the refractive index and the nonlinear coefficient has been introduced to quantify the fraction of molecules modified by ion implantation. Furthermore, a first electro-optic modulation in ion implanted DAST waveguides has been demonstrated.