Laser und Detektoren für THz-Anwendungen (2008)
Richter, Heiko, Böttger, Ute, Pavlov, Sergey, Semenov, Alexei, Hübers, Heinz-Wilhelm
Richter, Heiko, Semenov, Alexei, Pavlov, Sergei, Mahler, Lukas, Tredicucci, Alessandro, Beere, Harvey E., ...
A liquid cryogen free terahertz (THz) heterodyne receiver in a pulse tube cooler has been realized. The receiver operates at 2.5 THz. It is based on a quantum cascade laser (QCL) as local oscillator...
Richter, Heiko, Pavlov, Sergey, Semenov, Alexei, Hübers, Heinz-Wilhelm, Ill'in, Konstantin, Siegel, Michael, ...
Hübers, Heinz-Wilhelm, Pavlov, Sergej, Richter, Heiko, Semenov, Alexei, Mahler, L., Tredicucci, A., ...
The terahertz (THz) portion of the elctromagnetic spectrum bears an amazing scientific potential in astronomy. High resolution spectroscopy in particular heterodyne spectroscopy of molecular...
Laser Local Oscillators for Heterodyne Receivers beyond 2 Terahertz (2008)
Hübers, Heinz-Wilhelm, Richter, Heiko, Pavlov, Sergey, Semenov, Alexei, Tredicucci, Alessandro, Mahler, Lucas, ...
The design and performance of a local oscillator (LO) for an airborne terahertz heterodyne receiver is reported. The LO is based on a THz gas laser, which is transversely excited by radiation from a...
Temperature- and field-dependence of critical currents in NbN microbridges (2008)
Engel, Andreas, Bartolf, Holger, Schilling, Andreas, Ilin, Konstantin, Siegel, Michael, Semenov, Alexei, ...
We report measurements of the critical current of nano- and micrometer-sized NbN bridges as a function of temperature and magnetic eld. The bridges were fabricated from 4 to 10 nm thick, sputtered...
Ultra-thin NbN films on Si: crystalline and superconducting properties (2008)
Ilin, Konstantin, Schneider, R, Gerthsen, D, Engel, Andreas, Bartolf, Holger, Schilling, Andreas, ...
We present results on superconducting and crystalline properties of NbN films with a thickness smaller than 10 nm. The films were deposited using reactive magnetron sputtering on heated silicon...
Alexei Semenov, Alexandre Yakovlev
partial orders and symbolic traversal for efficient
Department of Computing Science, (2007)
Alexei Semenov, Alexandre Yakovlev
Obtaining a compact representation of the behaviour specified by Labelled Petri nets is an important part in verification of asynchronous circuit model at both abstract and logic synthesis levels....
16 Pixel HEB Heterodyne Mixer Array for 2.5 THz (2007)
Drakinskiy, Vladimir, Cherednichenko, Sergey, Berg, Terese, Hübers, Heinz-Wilhelm, Semenov, Alexei, Baubert, Jean, ...
A 16 pixel heterodyne receiver for 2.5 THz has been developed based on NbN superconducting hot-electron bolometer (HEB) mixers. The receiver uses a quasioptical RF coupling approach where HEB mixers...
Intermediate Frequency Bandwidth of a Hot-Electron Mixer: Comparison with Bolometric Models (2007)
Semenov, Alexei, Richter, Heiko, Pavlov, Sergey, Hübers, Heinz-Wilhelm, Il'in, Konstantin, Siegel, Michael, ...
The gain bandwidth of a superconducting NbN hot-electron mixer quasioptically coupled to radiation was evaluated in different operation conditions and compared to presently known bolometric mixer...
Spectral Sensistivity and Spectral Resolution of Superconducting Single-Photon Detectors (2007)
Haas, Philipp Moritz, Semenov, Alexei, Hübers, Heinz-Wilhelm, Beyer, Jörn, Kirste, Alexander, Schurig, Thomas, ...
Single photon detectors based on meanders from 5-nm thin B1 niobium nitride nanostrips show moderate spectral resolution along with the spectral cut-off of the quantum efficiency occurring in the...
Energieauflösung und spektrale Empfindlichkeit supraleitender Einzelphotonenzähler (2006)
Haas, Philipp Moritz, Semenov, Alexei, Hübers, Heinz-Wilhelm, Beyer, Jörn, Kirste, Alexander, Schurig, Thomas, ...
Hochempfindliche, ultraschnelle NbN-Einzelphotonenzähler, basierend auf der kurzzeitigen bias-stromunterstützten Ausbildung eines normal leitenden Bereichs (Hot-Spot) durch Photonenabsorption in...
Schnelle SQUID-basierte Ausleseelektronik für Nanostrukturierte Einzelphotonenzähler (2006)
Kirste, Alexander, Drung, Dietmar, Beyer, Jörn, Ruede, Frank, Aßmann, Cornelia, Peters, Margret, ...
Wir berichten über die Eigenschaften von rauscharmen, an der PTB entwickelten SQUID-Stromsensoren sowie deren Anwendung für die Auslesung von nanostrukturierten Hot-Spot-Detektoren. Die hierfür...
Spectral characterization of a 2.5 THz multi-mode quantum cascade laser (2006)
Pavlov, Sergey, Hübers, Heinz-Wilhelm, Richter, Heiko, Semenov, Alexei, Tredicucci, Alessandro, Köhler, Rüdeger, ...
Recently, terahertz-range semiconductor quantum cascade lasers (QCL) have attracted attention as potential local oscillators in heterodyne receivers. The basic characterization of the lasers, such as...
Semenov, Alexei, Engel, Andreas, Hübers, Heinz-Wilhelm, Ilin, Konstantin, Siegel, Michael
We have studied supercurrent-assisted formation of the resistive state in nano-structured Nb and NbN superconducting films after absorption of a single photon. In amorphous narrow NbN strips the...
Performance of the Phonon-Cooled Hot-Electron Bolometric Mixer Between 0.7 THz and 5.2 THz (2002)
Huebers, Heinz, Semenov, Alexei, Schubert, Josef, Gol'tsman, Greogry, Voronov, Boris
We report on the phonon cooled NbN hot electron bolometer as mixer in the terahertz frequency range. Its hybrid antenna consists of a hyperhemispheric silicon lens and a logarithmic-spiral feed...
Verification and synthesis of asynchronous control circuits using petri net unfoldings / (1997)
Thesis (Ph. D.)--University of Newcastle upon Tyne, 1997.