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| Author | Semenov, A. D.; Goghidze, I. G.; Gol’tsman, G. N.; Sergeev, A. V.; Aksaev, E. E.; Gershenzon, E. M. | ||||
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 | 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. | ||||
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| 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 | Khosropanah, Pourya | ||||
| 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 | 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. |
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| Address | |||||
| Corporate Author | Thesis | Ph.D. thesis | |||
| Publisher | Chalmers University of Technology | Place of Publication | Göteborg | Editor | |
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 910 | |||
| Permanent link to this record | |||||
| Author | Lieberzeit, P.; Afzal, A.; Rehman, A.; Dickert, F. | ||||
| Title |
Nanoparticles for detecting pollutants and degradation processes with mass-sensitive sensors | Type | Journal Article | ||
| Year | 2007 | Publication | Sensors and Actuators B: Chemical | Abbreviated Journal | Sensors and Actuators B: Chemical |
| Volume | 127 | Issue | 1 | Pages | 132-136 |
| Keywords | molecular imprinted polymer, MIP, recognition, quartz crystal microbalance, QCM, mass-sensitive sensor, detector | ||||
| Abstract | Compared with thin films, nanoparticle layers as coatings for QCM offer substantially increased interaction areas and sensitivities with favourable response times. Molybdenum disulphide (MoS2), e.g. has turned out to be a highly suitable material for interacting with thiols. The resulting materials are sufficiently soft according to Pearson to bind sulphur containing compounds reversibly. Depositing MoS2 nanoparticle submonolayers (particle size 200–300 nm) leads to an increase in sensor response by a factor of ten compared to a pure gold layer. Additionally, the nanoparticle layers show fully reversible sensor signals. Particle synthesis can also be combined with the molecular imprinting approach: by a precipitation technique, it is possible to generate molecularly imprinted TiO2 particles for engine oil degradation measurements. Compared with deposited thin layers, particles incorporate oxidised compounds from lubricants by a factor of two better. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-4005 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 568 | |||
| Permanent link to this record | |||||
| Author | Doerr, C.R.; Zhang, C.; Winzer, P.J. | ||||
| Title |
Monolithic InP multi-wavelength coherent receiver | Type | Conference Article | ||
| Year | 2010 | Publication | Conference on optical fiber communication, collocated national fiber optic engineers conference | Abbreviated Journal | Conf. OFC/NFOEC |
| Volume | Issue | Pages | 1-3 | ||
| Keywords | InP balanced detector, waveguide grating, polarization splitter, from chiralphotonics | ||||
| Abstract | We propose and demonstrate a novel four-channel monolithic polarization-diversity dual-quadrature coherent receiver with balanced detection in InP. It uses an interleave-chirped arrayed waveguide grating that acts simultaneously as a demultiplexer, 90° hybrid, and polarization splitter. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 851 | |||
| Permanent link to this record | |||||
| Author | Gershenson, M. E.; Gong, D.; Sato, T.; Karasik, B. S.; Sergeev, A. V. | ||||
| Title |
Millisecond electron-phonon relaxation in ultrathin disordered metal films at millikelvin temperatures | Type | Journal Article | ||
| Year | 2001 | Publication | Appl. Phys. Lett. | Abbreviated Journal | |
| Volume | 79 | Issue | Pages | 2049-2051 | |
| Keywords | HEB detector, FIR, far infrared | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ s @ heb_eph_interaction_Gershenzon | Serial | 315 | ||
| Permanent link to this record | |||||