Alcatel N.v.

Nec Corporation

Alcatel

Alcatel Alsthom Compagnie Generale D'electricite

Wilfried Idler

Michael Schilling

Klaus Wunstel

Dieter Baums

Olaf Hildebrand

Gert Laube

Kaspar Dutting

Yann Frignac

Eugen Lach

S&eacute;bastien Bigo

Sébastien Bigo

Heinz Schweizer

Karin Grosskopf

The invention shows a transmission system with a transmitter function, a transmitting fiber and a receiver function where the transmitter function comprising lightsources (), modulators () and a multiplexer (), and the receiver comprising at least a demultiplexer (), filters and electrical receivers where the channels for left side filtering are modulated with modulators with a negative chirp and for right side filtering with modulators with positive chirp.

Modulation scheme and transmission system for NRZ signals with left and right side filtering

A frequency allocation scheme for optical channels transmitted via a WDM transmission line with alternating left side and right side filtering for adjacent channels, with alternating channel spacing of A and B, where A<B, and with two sets of channels orthogonally polarized.

Frequency allocation scheme and transmission system for polarization and wavelength division multiplexed signals with left and right side filtering

An integrated optoelectronic semiconductor component is presented, which can equally process light signals of any polarization direction. Such semiconductor components are used for digital optical telecommunications. The semiconductor component has active (A) and passive (B) waveguide sections, which comprise a number of semiconductor layers (SP) with so-called multiple quantum well structures. The semiconductor layers (SP) are deposited by a process known as selective area growth (SAG). A portion of the semiconductor layers has a lattice constant which is smaller than the lattice constant of a substrate (SUB). This creates a biaxial tensile strain in these layers. The tensile strain is optimized in the active waveguide sections (A) to attain polarization independence. Furthermore a process is described whereby such a semiconductor component can be manufactured.

Monolithic integrated optoelectronic semiconductor component and process

A semiconductor device is operated as an optical filter. The semiconductor device has a substrate and a monolithically integrated branched waveguide structure disposed above the substrate, portions of the waveguide structure being divided into a plurality of regions by troughs, one of the regions being a branching region. Light is radiated into the waveguide structure at an end face of one of the regions and currents that are smaller than respective laser threshold currents of the regions flow through the regions, including the branching region, perpendicular to a propagation direction of light through the waveguide.

Method of operating a semiconductor device as an optical filter and

A semiconductor laser is provided monolithically integrated on a substrate and has a cavity layer extending above a plane that is coplanar with a base surface of the substrate, is branched and includes a plurality of separately controllable regions. The laser is operated by changing charge carrier density in at least one of the regions so that it emits light at one of a first wavelength and a second wavelength in correspondence with the charge carrier density change.

Method of operating a semiconductor laser as a bistable opto-electronic

An interferometric semiconductor laser includes a cavity in the form of a Y and at east three individually actuatable active segments. A central segment couples together the individually actuatable active segments. The central segment is an active or passive segment that acts as a beam divider. The arrangement of the segments forms two resonator paths which contain at least one common active segment. At least one resonator path includes an active segment that does not belong to the other resonator path. In the absence of, or with the same actuation of the active segments, the optical path length of one resonator path differs from the optical path length of the other resonator path.

Tunable semiconductor laser

A semiconductor laser that is monolithically integrated on a substrate and whose cavity has a branched structure that is simply contiguous in a topological sense, and which includes a plurality of regions that enclose the cavity, is operated as a mode-locked semiconductor laser, with an alternating current flowing through at least one region in addition to a direct current. The frequency of the alternating current is related to the reciprocal of the round-trip time or an integral multiple of this reciprocal of light pulses generated by the alternating current in the semiconductor laser.

Method of operating a semiconductor laser as a mode-locked semiconductor

Optically controllable semiconductor laser

In the commonly used methods for the coating of opto-electronic components, especially of semiconductor lasers, the layer thickness of a layer that is to be deposited is measured optically. The optical signal is converted into an electrical one with which the coating is controlled. The invention relates to the purely electrical interpretation of the high frequency component of the electrical noise power of an opto-electronic component (3) when a direct current passes through it. From the noise power, a controlling computer (10) derives a signal for control of the layer thickness; this is fed into a coating apparatus (14) of a coating reactor (2) which has a reacting chamber (1) containing the component (3) to be coated.

Growing community of inventors

Asperg, Germany

Wilfried Idler