toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Semenov, A. D.; Goghidze, I. G.; Gol’tsman, G. N.; Sergeev, A. V.; Aksaev, E. E.; Gershenzon, E. M. url  doi
openurl 
  Title Non-equilibrium quasiparticle response to radiation and bolometric effect in YBaCuO films Type Journal Article
  Year 1993 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 3 Issue 1 Pages 2132-2135  
  Keywords YBCO HTS HEB detectors  
  Abstract (down) The voltage photoresponse of structured current biased YBCO films on different substrates to 20-ps laser pulses of 0.63- mu m and 1.54- mu m wavelengths and to continuously modulated radiation of 2-mm wavelength is measured to temperatures around Tc. Fast picosecond decay of the response to pulsed radiation is followed by slow exponential relaxation with a nanosecond characteristic time depending on the substrate material and film dimensions. The slow component does not depend on wavelength and is attributed to the bolometric effect, while the magnitude of the fast component associated with nonequilibrium response rises with wavelength. More than an order-of-magnitude increase of the nonequilibrium response is seen from near-infrared to millimeter-wave range. This dependence plausibly reflects the low efficiency of multiplication of photoexcited electrons in YBaCuO compared to conventional superconductors.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1558-2515 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1659  
Permanent link to this record
 

 
Author Gol’tsman, G. N.; Kouminov, P. B.; Goghidze, I. G.; Karasik, B. S.; Gershenzon, E. M. url  doi
openurl 
  Title Nonbolometric and fast bolometric responses of YBaCuO thin films in superconducting, resistive, and normal states Type Conference Article
  Year 1994 Publication Proc. SPIE Abbreviated Journal Proc. SPIE  
  Volume 2159 Issue Pages 81-86  
  Keywords YBCO HTS HEB, nonbolornetric  
  Abstract (down) The transient voltage response in both epitaxial and granular YBaCuO thin films to 20 ps pulses of YAG:Nd laser radiation with 0.63 micrometers and 1.54 micrometers was studied. In normal and resistive states both types of films demonstrate two components: nonequilibrium picosecond component and following bolometric nanosecond. The normalized amplitudes are almost the same for all films. In superconducting state we observed a kinetic inductive response and two-component shape after integration. The normalized amplitude of the response in granular films is up to several orders of magnitude larger than in epitaxial films. We interpret the nonequilibrium response in terms of a suppression of order parameter by the excess of quasiparticles followed by the change of resistance in normal and resistive states or kinetic inductance in superconducting state. The sharp rise of inductive response in granular films is explained both by a diminishing of the crossection for current percolation through the disordered network os Josephson weak links and by a decrease of condensate density in neighboring regions.  
  Address  
  Corporate Author Thesis  
  Publisher SPIE Place of Publication Editor Nahum, M.; Villegier, J.-C.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference High-Temperature Superconducting Detectors: Bolometric and Nonbolometric  
  Notes Approved no  
  Call Number Serial 1641  
Permanent link to this record
 

 
Author Hübers, H.-W.; Semenov, A.; Holldack, K.; Schade, U.; Wüstefeld, G.; Gol’tsman, G. url  doi
openurl 
  Title Time domain analysis of coherent terahertz synchrotron radiation Type Journal Article
  Year 2005 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.  
  Volume 87 Issue 18 Pages 184103 (1 to 3)  
  Keywords NbN HEB mixers, applications  
  Abstract (down) The time structure of coherent terahertz synchrotron radiation at the electron storage ring of the Berliner Elektronensynchrotron und Speicherring Gesellschaft has been analyzed with a fast superconducting hot-electron bolometer. The emission from a single bunch of electrons was found to last ∼1500ps at frequencies around 0.4THz, which is much longer than the length of an electron bunch in the time domain (∼5ps). It is suggested that this is caused by multiple reflections at the walls of the beam line. The quadratic increase of the power with the number of electrons in the bunch as predicted for coherent synchrotron radiation and the transition from stable to bursting radiation were determined from a single storage ring fill pattern of bunches with different populations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1457  
Permanent link to this record
 

 
Author Khosropanah, Pourya openurl 
  Title NbN and NbTiN hot electron bolometer THz mixers Type Book Whole
  Year 2003 Publication Chalmers University of Technology Abbreviated Journal  
  Volume Issue Pages  
  Keywords HEB mixer, hot electron bolometer mixer, NbN, NbTiN, superconducting detector, heterodyne receiver, THz mixer, submillimeter mixer, quasioptical receiver, double slot antenna, twin slot antenna, spiral antenna, receiver noise, FTS, Fourier Transform Spectrometer  
  Abstract (down) The thesis reports the development of Hot Electron Bolometer (HEB) mixers for radio astronomy heterodyne receivers in THz frequency range. Part of this work is the fabrication of HEB devices, which are based on NbN or NbTiN superconducting thin films (â‰<a4>5 nm). They are integrated with wideband spiral or double-slot planar antennas. The mixer chips are incorporated into a quasi-optical receiver. The experimental part of this work focuses on the characterization of the receiver as a whole, and the HEB mixers as a part. Double side band receiver noise temperature and the IF bandwidth are reported for frequencies from 0.7 THz up to 2.6 THz. The spectrum of the direct response of HEB integrated with dierent antennas are measured using Fourier Transform Spectrometer (FTS). The effect of the bolometer size on total receiver performance and the LO power requirements is also discussed. A high-yield and reliable process for fabrication of NbN HEB mixers have been achieved. Over 100 devices with different bolometer geometry, film property and also different antennas have been fabricated and measured. The measured data enables us to discuss the impact of different parameters to the receiver overall performance.

This work has provided NbN HEB mixers to the following receivers:

TREND (Terahertz REceiver with NbN HEB Device) operating at 1.25-1.5 THz, installed in AST/RO Submillimeter Wave Telescope, Amundsen/Scott South Pole Station, in 2002-2003.

Band 6-low (1.410-1.700 THz) and 6-high (1.700-1.920 THz) of the HIFI (Heterodyne Instrument for Far Infra-red) in the Herschel Space Observatory, due to launch in 2007 by ESA (European Space Agency).

Besides, there has been continuous efforts to develop better models to explain the mixer performance more accurately. They are based on two temperature model for electrons and phonons and solving one-dimensional heat balance equations along the bolometer. The principles of these models are illustrated and the calculated results are compared with measured data.
 
  Address  
  Corporate Author Thesis Ph.D. thesis  
  Publisher Chalmers University of Technology Place of Publication Göteborg Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 910  
Permanent link to this record
 

 
Author Trifonov, A.; Tong, C.-Y. E.; Lobanov, Y.; Kaurova, N.; Blundell, R.; Goltsman, G. url  doi
openurl 
  Title Photon absorption near the gap frequency in a hot electron bolometer Type Journal Article
  Year 2017 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.  
  Volume 27 Issue 4 Pages 1-4  
  Keywords NBN HEB mixer  
  Abstract (down) The superconducting energy gap is a fundamental characteristic of a superconducting film, which, together with the applied pump power and the biasing setup, defines the instantaneous resistive state of the Hot Electron Bolometer (HEB) mixer at any given bias point on the I-V curve. In this paper we report on a series of experiments, in which we subjected the HEB to radiation over a wide frequency range along with parallel microwave injection. We have observed three distinct regimes of operation of the HEB, depending on whether the radiation is above the gap frequency, far below it or close to it. These regimes are driven by the different patterns of photon absorption. The experiments have allowed us to derive the approximate gap frequency of the device under test as about 585 GHz. Microwave injection was used to probe the HEB impedance. Spontaneous switching between the superconducting (low resistive) state and a quasi-normal (high resistive) state was observed. The switching pattern depends on the particular regime of HEB operation and can assume a random pattern at pump frequencies below the gap to a regular relaxation oscillation running at a few MHz when pumped above the gap.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1558-2515 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Serial 1331  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: