Abstract: An electro-optical modulator with two electrodes as part of a transmission line of a first phase modulator and two electrodes as part of a transmission line of a second phase modulator included in two arms of a Mach-Zehnder-interferometer. An electrical controller applies a first electrical high-frequency-modulated voltage signals between the first and second electrodes and applies a second electrical high-frequency-modulated signals between the fourth and third electrodes. The electrical controller applies signals such that voltages applied to the first and fourth electrodes have substantially a same high-frequency content, and voltages applied to the second and third electrodes have substantially the same high-frequency content. In such configuration, a constant voltage offset is produced by either the voltages applied to the first and fourth electrodes or, the second and third electrodes. Thereby, cross-talk between electrodes, electrical losses, device size and fabrication costs may be reduced.

Abstract: A THz antenna array has a plurality of THz antennae, a THz antenna having a photoconductive region and a first electrode and a second electrode which are arranged interspaced from each other via a spacer region that extends laterally across at least a part of the photoconductive region. In order to simplify the structure and facilitate its production, a lateral region between adjacent THz antennae of the array is not photoconductive. It is especially free from photoconductive material.