We present two 8/spl times/170 Gbit/s DWDM/OTDM (1.28 Tbit/s) field transmission experiment both over more than 400 km in commercially operated legacy networks of France Telecom (FT) and Deutsche Telekom (DT), respectively. Conventional EDFA based amplification schemes as well as distributed Raman amplified systems are tested. For different levels of polarization mode dispersion due to different quality of the installed fibre infrastructure adaptive PMD compensation and polarization de-multiplexing is tested.

To achieve ultra-high bit rate signal beyond existing ETDM technology optical time division multiplexing (OTDM) is been used. In this paper the various applications of electroabsorption modulators in transmitters and receivers in ultra-high speed OTDM-based transmission systems is reviewed. Results of single channel and DWDM fiber transmission experiments are presented.

We present a 8×170 Gbit/s DWDM/OTDM (1.28 Tbit/s) field transmission experiment over 421 km in commercially operated network of Deutsche Telekom. Stable transmission performance was achieved for all channels with BER ≤ 2.8*10-4 using adaptive PMD compensation.

We report on the impact of PMD in a 8/spl times/170 Gbit/s DWDM transmission experiment over 430 km field installed SSMF with and without PMD compensation. Stable performance is only achieved when using PMDC.

We report on adaptive PMD (polarisation mode dispersion) compensation in a 170 Gbit/s RZ transmission system with alternating polarisation. The PMD tolerance is significantly improved using an asymmetric rather than symmetric setup of the two-stage PMD compensator.

This paper gives an overview of key technologies applied for realisation of a 8×170Gbit/s DWDM system demonstrator and summarizes results of transmission experiments with Terabit/s capacity over long-haul distances over European fibre infrastructure.

We report on adaptive optical PMD compensation (OPMDC) at 160Gbit/s RZ transmission using electrical spectral line power and eye monitor feedback signals. A 4-decade improvement of BER is achieved by using post demux eye monitor feedback.

A planar lightwave polarization stabilizer concept has been proposed which is based on a multi-feedback scheme providing individual and bipolar feedback signals for each of the phase shifters of the integrated optic waveguide structure. This allows for fast adaptation to changing input state of polarization and simple adaptation control. In part this feedback scheme has experimentally been confirmed by showing no receiver sensitivity degradation after stabilizing an 80 Gb/s RZ signal with changing polarization at the input port of a polarization sensitive OTDM receiver. Extension of the proposed feedback scheme to a planar PMD compensator was discussed by numerical simulation showing that pattern correlation and fast optical gates are required.

We have demonstrated an advanced 160 Gbit/s OTDM transmission system with a wavelength transparent transmitter concept suitable for DWDM operation. Latest 40 Gbit/s ETDM technology is used for the first time both in the 160 Gbit/s transmitter and receiver along with PLL clock recovery. 160 Gbit/s OTDM transmission has been demonstrated over 2 /spl times/ 100 km of TeraLight/spl trade/ fibre without an error floor. The experiments clearly show that long TeraLight/spl trade/ fibre spans can be bridged without the need for Raman-amplification.

We have demonstrated an advanced 160 Gbit/s OTDM transmission system with a wavelength transparent transmitter concept suitable for DWDM operation. Latest 40 Gbit/s ETDM technology is used for the first time both in the 160 Gbit/s transmitter and receiver along with PLL clock recovery. 160 Gbit/s OTDM transmission has been demonstrated over 2 × 100 km of TeraLight™ fibre without an error floor. The experiments clearly show that long TeraLight™ fibre spans can be bridged without the need for Raman-amplification.

Statistical PMD compensation experiments have been performed at 160 Gb/s bitrate using a simple compensator with eye monitor feedback after demux. Even for spectral wide RZ signals a clear improvement of bit error rate by 1½ decade has been demonstrated.

Fluorescent objects closer than the diffraction resolution limit can be distinguished in far-field microscopy provided they feature different emission spectra. Utilizing the superior axial resolution of 4Pi-confocal microscopy of 100–150 nm, we investigate the precision with which fluorescence objects with subdiffraction axial distance can be measured in the far field. At a wavelength of 820 nm distances on the order of 60 nm between beads and a monomolecular Langmuir–Blodgett layer were determined with a precision of 1.2 nm within 3.2 s. The reduced spatial extent of the 4Pi-confocal point-spread-function improves the precision of colocalization measurements in double stained specimens and opens up the prospect on far-field fluorescence profilometry with (sub) nanometer height resolution.