Regensburg 2007 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 19: Symposium “Terahertz Detectors”

TT 19.3: Talk

Wednesday, March 28, 2007, 15:20–15:50, H20

Terahertz detectors using hot-electrons in superconducting films — •Alexei Semenov — DLR Institute of Planetary Research, Berlin, Germany

Recently the terahertz gap has been recognized as a prospective spectral range for radoiastronomy as well as for material and security studies. Implementation of terahertz technology in these fields requires further improvement of instruments and their major subcomponents. Physical phenomena associated with the local and homogeneous non-equilibrium electron sates in thin superconducting films offer numerous possibilities for the development of terahertz and infrared detectors. Depending on the nature of the resistive state and the operation regime, a variety of detector can be realized. They are e.g. direct bolometric or kinetic inductance detectors, heterodyne mixers or photon counters. Operation principles and physical limitations of these devices will be discussed. Two examples of the detector development made in cooperation between the German Aerospace Center, the University of Karlsruhe and PTB, Berlin will be presented. The energy resolving single-photon detector with an almost fundamentally limited energy resolution of 0.6 eV at 6.5 K for photons with wavelengths from 400 nm to 2500 nm and the heterodyne mixer quasioptically coupled to radiation in the frequency range from 0.8 THz to 5 THz and providing a noise temperature of less then ten times the quantum limit. The mixers will be implemented in the terahertz radar for security screening (TERASEC) and in the heterodyne receiver of the stratospheric observatory SOFIA.