Fraunhofer-gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Thorsten Göbel

Roman J Dietz

Björn Globisch

Mykhaylo Semtsiv

Karl-Otto Velthaus

William Ted Masselink

Jung Han Choi

Roman Dietz

Roman J B Dietz

W Ted Masselink

Mykhaylo Petrovych Semtsiv

A terahertz transceiver, comprising at least a first and a second antenna, wherein the first and/or the second antenna is a dipole antenna comprising a dipole section, wherein the dipole section has a gap through which light can be radiated onto the photoconductive material, and wherein a first ending of the dipole section is connected to a first feedline and a second ending of the dipole section is connected to a second feedline, the feedlines (extending with an angle to the dipole section. The first and/or the second antenna has an asymmetric design, wherein a first section of at least one of the feedlines extending on one side of the dipole section is longer than a second section of the at least one feedline extending on the other side of the dipole section and/or at least one of the feedlines extends on one side of the dipole section, only.

Terahertz transceivers

A photoconductor for emitting and/or receiving electromagnetic waves is provided. The photoconductor comprises a material region comprising a first and a second section, wherein the second section provides a higher density of charge carrier trapping centers and/or recombination centers than the first section, and a confinement generating a sub-band structure of the charge carrier energy states in the material region. The first and the second section are arranged and configured in such a manner that a maximum of the carrier probability density of the sub-band ground state is located in one of these sections and a maximum of the carrier probability density of an excited sub-band state is located in the respective other section.

Photoconductor for emitting and/or receiving electromagnetic waves

A terahertz antenna includes at least one photoconductive layer which generates charge carriers upon irradiation of light and two electroconductive antenna elements via which an electric field can be applied to at least one section of the photoconductive layer. The photoconductive layer being doped with a dopant in a concentration of at least 1&#xd7;1018 cm&#x2212;3, the dopant being a transition metal. The photoconductive layer is produced by molecular beam epitaxy at a growth temperature of at least 200&#xb0; C. and not more than 500&#xb0; C., the dopant being arranged in the photoconductive layer such that it produces a plurality of point defects.

Terahertz antenna and method for producing a terahertz antenna

It is provided a system for determining characteristics of an object or a sample comprising at least a first and a second transmitter unit, wherein the first transmitter unit is configured for transmitting first electromagnetic waves towards the object and the second transmitter unit is configured for transmitting second electromagnetic waves towards the object; at least one receiver unit) for receiving electromagnetic waves from the object, the receiver unit generating a receiver signal upon receipt of the electromagnetic waves from the object. The first and the second transmitter unit is configured in such a way that the first and the second electromagnetic waves are modulated differently in such a way that by demodulating the receiver signal, a portion of the receiver signal evoked by the first electromagnetic waves can be separated from a portion of the receiver signal evoked by the second electromagnetic waves. The system comprises an evaluating unit.

System and method for determining characteristics of an object or a sample

It is provided a vectorial network analyzer, comprising an input and output measuring device; a beat source for generating an optical beat signal; an optical transmission device which divides the optical beat signal into at least one first and one second partial signal, wherein the transmission device conducts the first partial signal to at least one terahertz transmitter and the second partial signal to at least one terahertz receiver and/or to at least one terahertz reference receiver; and a phase changing unit for varying the phase of the first and/or the second partial signal of the optical beat signal.

Growing community of inventors

Berlin, Germany

Thorsten Göbel