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Author Il'in, K. S.; Lindgren, M.; Currie, M. A.; Semenov, D.; Gol'tsman, G. N.; Sobolewski, Roman; Cherednichenko, S. I.; Gershenzon, E. M.
Title Picosecond hot-electron energy relaxation in NbN superconducting photodetectors Type Journal Article
Year 2000 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 76 Issue 19 Pages 2752-2754
Keywords NbN HEB detectors, two-temperature model, IF bandwidth
Abstract We report time-resolved characterization of superconducting NbN hot-electron photodetectors using an electro-optic sampling method. Our samples were patterned into micron-size microbridges from 3.5-nm-thick NbN films deposited on sapphire substrates. The devices were illuminated with 100 fs optical pulses, and the photoresponse was measured in the ambient temperature range between 2.15 and 10.6 K (superconducting temperature transition TC). The experimental data agreed very well with the nonequilibrium hot-electron, two-temperature model. The quasiparticle thermalization time was ambient temperature independent and was measured to be 6.5 ps. The inelastic electron–phonon scattering time Ï„e–ph tended to decrease with the temperature increase, although its change remained within the experimental error, while the phonon escape time Ï„es decreased almost by a factor of two when the sample was put in direct contact with superfluid helium. Specifically, Ï„e–ph and Ï„es, fitted by the two-temperature model, were equal to 11.6 and 21 ps at 2.15 K, and 10(±2) and 38 ps at 10.5 K, respectively. The obtained value of Ï„e–ph shows that the maximum intermediate frequency bandwidth of NbN hot-electron phonon-cooled mixers operating at TC can reach 16(+4/–3) GHz if one eliminates the bolometric phonon-heating effect.
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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 (up) 0003-6951 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 856
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Author Semenov, A. D.; Goghidze, I. G.; Gol’tsman, G. N.; Sergeev, A. V.; Gershenzon, E. M.
Title Evidence for the spectral dependence of nonequilibrium picosecond photoresponse of YBaCuO thin films Type Journal Article
Year 1993 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 63 Issue 5 Pages 681-683
Keywords YBCO HTS detectors, nonequilibrium
Abstract The transient voltage photoresponse of current biased YBaCuO thin films to 20 ps laser pulses of 0.63 and 1.54 μm wavelengths is measured for temperatures around the superconducting transition region. The fast picosecond decay of the response is followed by a slow nanosecond relaxation which is associated with the bolometric effect. The magnitude of the fast component of the response varies in proportion to the square root of wavelength that plausibly reflects multiplication processes of photoexcited electrons via electron–electron scattering and interaction with high energy phonons.
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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 (up) 0003-6951 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1655
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Author Semenov, A. D.; Gol’tsman, G. N.; Gogidze, I. G.; Sergeev, A. V.; Gershenzon, E. M.; Lang, P. T.; Renk, K. F.
Title Subnanosecond photoresponse of a YBaCuO thin film to infrared and visible radiation by quasiparticle induced suppression of superconductivity Type Journal Article
Year 1992 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 60 Issue 7 Pages 903-905
Keywords YBCO HTS detectors
Abstract We observed subnanosecond photoresponse of a structured superconducting YBa2Cu3O7−δ thin film to infrared and visible radiation. We measured the voltage response of a current biased film (thickness 700 Å) in a resistive state to radiation pulses. From our results we conclude a response time of about 90 ps and a responsivity of about 4×1010 Ω/J. We attribute the response to Cooper pair breaking and suppression of the superconducting energy gap induced by nonequilibrium quasiparticles.
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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 (up) 0003-6951 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1672
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Author Dube, I.; Jiménez, D.; Fedorov, G.; Boyd, A.; Gayduchenko, I.; Paranjape, M.; Barbara, P.
Title Understanding the electrical response and sensing mechanism of carbon-nanotube-based gas sensors Type Journal Article
Year 2015 Publication Carbon Abbreviated Journal Carbon
Volume 87 Issue Pages 330-337
Keywords carbon nanotubes, CNT detectors, field effect transistors, FET
Abstract Gas sensors based on carbon nanotube field effect transistors (CNFETs) have outstanding sensitivity compared to existing technologies. However, the lack of understanding of the sensing mechanism has greatly hindered progress on calibration standards and customization of these nano-sensors. Calibration requires identifying fundamental transistor parameters and establishing how they vary in the presence of a gas. This work focuses on modeling the electrical response of CNTFETs in the presence of oxidizing (NO2) and reducing (NH3) gases and determining how the transistor characteristics are affected by gas-induced changes of contact properties, such as the Schottky barrier height and width, and by the doping level of the nanotube. From the theoretical fits of the experimental transfer characteristics at different concentrations of NO2 and NH3, we find that the CNTFET response can be modeled by introducing changes in the Schottky barrier height. These changes are directly related to the changes in the metal work function of the electrodes that we determine experimentally, independently, with a Kelvin probe. Our analysis yields a direct correlation between the ON – current and the changes in the electrode metal work function. Doping due to molecules adsorbed at the carbon-nanotube/metal interface also affects the transfer characteristics.
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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 (up) 0008-6223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1778
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Author Gershenzon, E. M.; Gershenzon, M. E.; Goltsman, G. N.; Semenov, A. D.; Sergeev, A. V.
Title Wide-band highspeed Nb and YBaCuO detectors Type Journal Article
Year 1991 Publication IEEE Trans. Magn. Abbreviated Journal IEEE Trans. Magn.
Volume 27 Issue 2 Pages 2836-2839
Keywords YBCO, HTS, Nb detectors
Abstract The physical limitations on the response time and the nature of nonequilibrium detection of radiation were investigated for Nb and YBCO film in a wide spectral range from millimeter to near-infrared wavelengths. In the case of ideal heat removal from the film, the detection mechanism is connected with an electron heating effect which is not selective over a wide spectral interval. For Nb, the dependence of the response time on the electron mean free path l and temperature T is tau varies as T/sup -2/l/sup -1/. The values of detectivity D* and tau are 3*10/sup 11/ W/sup -1/ Hz/sup 1/2/ cm and 5*10/sup -9/ s at T=1.6 K, respectively. For YBCO film the tau value of 1-2 ps at T=77 K was obtained; the NEP value of 3*10/sup -11/ W-Hz/sup -1/2/ can be obtained at T=77 K in the case of the optimal film matching to the radiation.
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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 (up) 0018-9464 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 239
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Author Lubzens, D.; Rosenfeld, D.; Nemirovsky, Y.
Title The noise equivalent temperature difference performance of HgCdTe photodiode array Type Journal Article
Year 1988 Publication Infrared Physics Abbreviated Journal Infrared Physics
Volume 28 Issue 6 Pages 417-423
Keywords HgCdTe detector array
Abstract
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 (up) 0020-0891 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 469
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Author Gayduchenko, I.; Kardakova, A.; Fedorov, G.; Voronov, B.; Finkel, M.; Jiménez, D.; Morozov, S.; Presniakov, M.; Goltsman, G.
Title Response of asymmetric carbon nanotube network devices to sub-terahertz and terahertz radiation Type Journal Article
Year 2015 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 118 Issue 19 Pages 194303
Keywords terahertz detectors, asymmetric carbon nanotubes, CNT
Abstract Demand for efficient terahertz radiation detectors resulted in intensive study of the asymmetric carbon nanostructures as a possible solution for that problem. It was maintained that photothermoelectric effect under certain conditions results in strong response of such devices to terahertz radiation even at room temperature. In this work, we investigate different mechanisms underlying the response of asymmetric carbon nanotube (CNT) based devices to sub-terahertz and terahertz radiation. Our structures are formed with CNT networks instead of individual CNTs so that effects probed are more generic and not caused by peculiarities of an individual nanoscale object. We conclude that the DC voltage response observed in our structures is not only thermal in origin. So called diode-type response caused by asymmetry of the device IV characteristic turns out to be dominant at room temperature. Quantitative analysis provides further routes for the optimization of the device configuration, which may result in appearance of novel terahertz radiation detectors.
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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 (up) 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1169
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Author Danerud, M.; Winkler, D.; Lindgren, M.; Zorin, M.; Trifonov, V.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E. M.
Title Nonequilibrium and bolometric photoresponse in patterned YBa2Cu3O7−δ thin films Type Journal Article
Year 1994 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 76 Issue 3 Pages 1902-1909
Keywords YBCO HTS HEB detector, nonequilibrium response
Abstract Epitaxial laser deposited YBa2Cu3O7−δ films of ∼50 nm thickness were patterned into detectors consisting of ten parallel 1 μm wide strips in order to study nonequilibrium and bolometric effects. Typically, the patterned samples had critical temperatures around 86 K, transition widths around 2 K and critical current densities above 1×106A/cm2 at 77 K. Pulsed laser measurements at 0.8 μm wavelength (17 ps full width at half maximum) showed a ∼30 ps response, attributed to electron heating, followed by a slower bolometric decay. Amplitude modulation in the band fmod=100 kHz–10 GHz of a laser with wavelength λ=0.8 μm showed two different thermal relaxations in the photoresponse. Phonon escape from the film (∼3 ns) is the limiting process, followed by heat diffusion in the substrate. Similar relaxations were also seen for λ=10.6 μm. The photoresponse measurements were made with the film in the resistive state and extended into the normal state. These states were created by supercritical bias currents. Measurements between 75 and 95 K (i.e., from below to above Tc) showed that the photoresponse was proportional to dR/dT for fmod=1 MHz and 4 GHz. The fast response is limited by the electron‐phonon scattering time, estimated to 1.8 ps from experimental data. The responsivity both at 0.8 and 10.6 μm wavelength was ∼1.2 V/W at fmod=1 GHz and the noise equivalent power was calculated to 1.5×10−9 WHz−1/2 for the fast response.
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 (up) 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1637
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Author Nebosis, R. S.; Steinke, R.; Lang, P. T.; Schatz, W.; Heusinger, M. A.; Renk, K. F.; Gol’tsman, G. N.; Karasik, B. S.; Semenov, A. D.; Gershenzon, E. M.
Title Picosecond YBa2Cu3O7−δdetector for far‐infrared radiation Type Journal Article
Year 1992 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 72 Issue 11 Pages 5496-5499
Keywords YBCO HTS detectors
Abstract We report on a picosecond YBa2Cu3O7−δ detector for far‐infrared radiation. The detector, consisting of a current carrying structure cooled to liquid‐nitrogen temperature, was studied by use of ultrashort laser pulses from an optically pumped far‐infrared laser in the frequency range from 25 to 215 cm−1. We found that the sensitivity (1 mV/W) was almost constant in this frequency range. We estimated a noise equivalent power of less than 5×10−7 W Hz−1/2. Taking into account the results of a mixing experiment (in the frequency range from 4 to 30 cm−1) we suggest that the response time of the detector was few picoseconds.
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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 (up) 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1668
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Author Ryzhii, V.; Otsuji, T.; Ryzhii, M.; Leiman, V. G.; Fedorov, G.; Goltzman, G. N.; Gayduchenko, I. A.; Titova, N.; Coquillat, D.; But, D.; Knap, W.; Mitin, V.; Shur, M. S.
Title Two-dimensional plasmons in lateral carbon nanotube network structures and their effect on the terahertz radiation detection Type Journal Article
Year 2016 Publication J. Appl. Phys. Abbreviated Journal J. Appl. Phys.
Volume 120 Issue 4 Pages 044501 (1 to 13)
Keywords carbon nanotubes, CNT detectors, plasmons
Abstract We consider the carrier transport and plasmonic phenomena in the lateral carbon nanotube (CNT) networks forming the device channel with asymmetric electrodes. One electrode is the Ohmic contact to the CNT network and the other contact is the Schottky contact. These structures can serve as detectors of the terahertz (THz) radiation. We develop the device model for collective response of the lateral CNT networks which comprise a mixture of randomly oriented semiconductor CNTs (s-CNTs) and quasi-metal CNTs (m-CNTs). The proposed model includes the concept of the collective two-dimensional (2D) plasmons in relatively dense networks of randomly oriented CNTs (CNT “felt”) and predicts the detector responsivity spectral characteristics exhibiting sharp resonant peaks at the signal frequencies corresponding to the 2D plasmonic resonances. The detection mechanism is the rectification of the ac current due the nonlinearity of the Schottky contact current-voltage characteristics under the conditions of a strong enhancement of the potential drop at this contact associated with the plasmon excitation. The detector responsivity depends on the fractions of the s- and m-CNTs. The burning of the near-contact regions of the m-CNTs or destruction of these CNTs leads to a marked increase in the responsivity in agreement with our experimental data. The resonant THz detectors with sufficiently dense lateral CNT networks can compete and surpass other THz detectors using plasmonic effects at room temperatures.
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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 (up) 0021-8979 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1777
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Author Bespalov, A.V.; Gol'tsman, G.N.; Semenov, A.D.; Renk, K.F.
Title Determination of the far-infrared emission characteristic of a cyclotron p-germanium laser by use of a superconducting Nb detector Type Journal Article
Year 1991 Publication Solid State Communications Abbreviated Journal Solid State Communications
Volume 80 Issue 7 Pages 503-506
Keywords Nb detector, applications
Abstract We studied the far-infrared emission characteristics of a cyclotron p-germanium laser using a broad-band superconducting Nb film detector. For magnetic fields between ∼25 kOe and ∼50 kOe, emission in a frequency range from ∼50 cm-1 to ∼100 cm-1 with maximum intensity around 90 cm-1 was obtained. We determined, for fixed magnetic fields, electric field dependences of the emission intensity taking into account that the total electric field is a sum of the applied and the Hall electric field. An analysis of the emission intensity characteristic gives evidence that transitions between the two lowest Landau levels of light holes are responsible for the laser action.
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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 (up) 0038-1098 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1677
Permanent link to this record
 
 
Author Gershenzon, E. M.; Gol'tsman, G. N.; Semenov, A. D.; Sergeev, A. V.
Title Mechanism of picosecond response of granular YBaCuO films to electromagnetic radiation Type Journal Article
Year 1990 Publication Solid State Communications Abbreviated Journal Solid State Communications
Volume 76 Issue 4 Pages 493-497
Keywords YBCO HTS detectors
Abstract The ultrafast mechanisms of radiation detection in granular YBaCuO films are studied in the wide wavelength range from millimeter to near infrared. With the rise of radiation frequency the Josephson detection at the grain boundary weak links is replaced by electron heating into the grains. This change occurs in the submillimeter wavelength range. Electron-phonon relaxation time τeph is determined by direct measurements and analyses quasistationary electron heating. Temperature dependence of τeph at T ≤ 40 K was found to be τeph ∼ T−1. The results show that detectors with the response time of few picoseconds at nitrogen temperature are attainable.
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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 (up) 0038-1098 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1685
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Author Voronov, B. M.; Gershenzon, E. M.; Gol'tsman, G. N.; Gogidze, I. G.; Gusev, Yu. P.; Zorin, M. A.; Sejdman, L. A.; Semenov, A. D.
Title Picosecond range detector base on superconducting niobium nitride film sensitive to radiation in spectral range from millimeter waves up to visible light Type Journal Article
Year 1992 Publication Sverkhprovodimost': Fizika, Khimiya, Tekhnika Abbreviated Journal Sverkhprovodimost': Fizika, Khimiya, Tekhnika
Volume 5 Issue 5 Pages 955-960
Keywords NbN HEB detectors
Abstract Fast-operating picosecond detector of electromagnetical radiation is developed on the basis of fine superconducting film of niobium nitride with high sensitivity within spectral range from millimetric waves up to visible light. Detector sensitive element represents structure covering narrow parallel strips with micron sizes included in the rupture of microstrip line. Detecting ability of the detector and time constant measured using amplitude-simulated radiation of reverse wave tubes and pulse radiation of picosecond gas and solid-body lasers, constitute D*≅1010 W-1·cm·Hz-1/2 and τ≤5 ps respectively, at 10 K temperature. The expected value of time constant of the detector at 10 K obtained via extrapolation of directly measured dependence that is, τ ∝ τ-1, constitutes 20 ps. Experimental data demonstrate that detection mechanism is linked with electron heating effect.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Russian Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0131-5366 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1670
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Author Gershenzon, E. M.; Gol'tsman, G. N.; Karasik, B. S.; Lugovaya, G. Ya.; Serebryakova, N. A.; Chinkova, E. V.
Title Infrared radiation detectors on the base of electron heating in resistive state films from traditional superconducing materials Type Journal Article
Year 1992 Publication Sverkhprovodimost': Fizika, Khimiya, Tekhnika Abbreviated Journal Sverkhprovodimost': Fizika, Khimiya, Tekhnika
Volume 5 Issue 6 Pages 1129-1140
Keywords IR HEB detectors
Abstract Characteristics of infrared radiation detectors based on electron heating in thin superconducting films transformed at T ≤ Tc to a resistive state by transport current and, if necessary, by magnetic field are investigated. A comparison is made of the characteristics of the detectors fabricated of different materials: aluminium, niobium, Mo0.5Re0.5. Some devices with different topology of the reception area are considered. Electron heating detectors are comparable by their sensitivity with superconducting bolometers, but differ in a high fast-response.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Russian Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0131-5366 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1673
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Author Nebosis, R. S.; Heusinger, M. A.; Semenov, A. D.; Lang, P. T.; Schatz, W.; Steinke, R.; Renk, K. F.; Gol'tsman, G. N.; Karasik, B. S.; Gershenzon, E. M.
Title Ultrafast photoresponse of an YBa2Cu3O7-δ film to far-infrared radiation pulses Type Journal Article
Year 1993 Publication Opt. Lett. Abbreviated Journal Opt. Lett.
Volume 18 Issue 2 Pages 96-97
Keywords YBCO HTS detectors
Abstract We report the observation of an ultrafast photoresponse of a high-T(c), film to far-infrared radiation pulses. The response of a sample, consisting of a current-carrying structured YBa(2)Cu(3)O(7-delta) film cooled to liquid-nitrogen temperature, was studied by use of ultrashort laser pulses from an optically pumped far-infrared laser in the frequency range from 0.7 to 7 THz. We found that the response time was limited by the time resolution, 120 ps, of our electronic registration equipment.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0146-9592 ISBN Medium
Area Expedition Conference
Notes PMID:19802049 Approved no
Call Number Serial 1660
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