|   | 
Details
   web
Records
Author Lobanov, Y.V.; Tong, C.-Y.E.; Hedden, A.S.; Blundell, R.; Voronov, B.M.; Gol'tsman, G.N.
Title Direct measurement of the gain and noise bandwidths of HEB mixers Type Journal Article
Year 2011 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume (down) 21 Issue 3 Pages 645-648
Keywords waveguide NbN HEB mixers
Abstract The intermediate frequency (IF) bandwidth of a hot electron bolometer (HEB) mixer is an important parameter of the mixer, in that it helps to determine its suitability for a given application. With the availability of wideband low noise amplifiers, it is simple to measure the performance of an HEB mixer over a wide range of IF at a fixed LO frequency using the standard Y-factor method. This in-situ method allows us to measure both the gain and noise bandwidths simultaneously. We have also measured mixer output impedance with a vector network analyser. Intrinsic time constant has been extracted from the impedance data and compared to the mixer's bandwidths determined from receiver Y-factor measurement.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 720
Permanent link to this record
 

 
Author Seleznev, V. A.; Tarkhov, M. A.; Voronov, B. M.; Milostnaya, I. I.; Lyakhno, V. Yu; Garbuz, A. S.; Mikhailov, M. Yu; Zhigalina, O. M.; Gol'tsman, G. N.
Title Deposition and characterization of few-nanometers-thick superconducting Mo-Re films Type Journal Article
Year 2008 Publication Supercond. Sci. Technol. Abbreviated Journal Supercond. Sci. Technol.
Volume (down) 21 Issue 11 Pages 115006 (1 to 6)
Keywords
Abstract We report on the fabrication and investigation of few-nanometers-thick superconducting molybdenum-rhenium (Mo-Re) films intended for use in nanowire single-photon superconducting detectors (SSPDs). Mo-Re films were deposited on sapphire substrates by DC magnetron sputtering of an Mo(60)-Re(40) alloy target in an atmosphere of argon. The films 2-10 nm thick had critical temperatures (Tc) from 5.6 to 9.7 K. HRTEM (high-resolution transmission electron microscopy) analysis showed that the films had a homogeneous structure. XPS (x-ray photoelectron spectroscopy) analysis showed the Mo to Re atom ratio to be 0.575/0.425, oxygen concentration to be 10%, and concentration of other elements to be 1%.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ gujma @ Serial 723
Permanent link to this record
 

 
Author Kovalyuk, V.; Hartmann, W.; Kahl, O.; Kaurova, N.; Korneev, A.; Goltsman, G.; Pernice, W. H. P.
Title Absorption engineering of NbN nanowires deposited on silicon nitride nanophotonic circuits Type Journal Article
Year 2013 Publication Opt. Express Abbreviated Journal Opt. Express
Volume (down) 21 Issue 19 Pages 22683-22692
Keywords SSPD, SNSPD, NbN nanoeires, Si3N4 waveguides
Abstract We investigate the absorption properties of U-shaped niobium nitride (NbN) nanowires atop nanophotonic circuits. Nanowires as narrow as 20nm are realized in direct contact with Si3N4 waveguides and their absorption properties are extracted through balanced measurements. We perform a full characterization of the absorption coefficient in dependence of length, width and separation of the fabricated nanowires, as well as for waveguides with different cross-section and etch depth. Our results show excellent agreement with finite-element analysis simulations for all considered parameters. The experimental data thus allows for optimizing absorption properties of emerging single-photon detectors co-integrated with telecom wavelength optical circuits.
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 1094-4087 ISBN Medium
Area Expedition Conference
Notes PMID:24104155 Approved no
Call Number Serial 1213
Permanent link to this record
 

 
Author Iomdina, E. N.; Goltsman, G. N.; Seliverstov, S. V.; Sianosyan, A. A.; Teplyakova, K. O.; Rusova, A. A.
Title Study of transmittance and reflectance spectra of the cornea and the sclera in the THz frequency range Type Journal Article
Year 2016 Publication J. Biomed. Opt. Abbreviated Journal J. Biomed. Opt.
Volume (down) 21 Issue 9 Pages 97002 (1 to 5)
Keywords BWO, IMPATT diode, Schottky diode, medicine, animals, cornea, physiology, humans, rabbits, sclera diagnostic imaging, physiology
Abstract An adequate water balance (hydration extent) is one of the basic factors of normal eye function, including its external shells: the cornea and the sclera. Adequate control of corneal and scleral hydration is very important for early diagnosis of a variety of eye diseases, stating indications for and contraindications against keratorefractive surgeries and the choice of contact lens correction solutions. THz systems of creating images in reflected beams are likely to become ideal instruments of noninvasive control of corneal and scleral hydration degrees. This paper reports on the results of a study involving transmittance and reflectance spectra for the cornea and the sclera of rabbit and human eyes, as well as those of the rabbit eye, in the frequency range of 0.13 to 0.32 THz. The dependence of the reflectance coefficient of these tissues on water mass percentage content was determined. The experiments were performed on three corneas, three rabbit scleras, two rabbit eyes, and three human scleras. The preliminary results demonstrate that the proposed technique, based on the use of a continuous THz radiation, may be utilized to create a device for noninvasive control of corneal and scleral hydration, which has clear potential of broad practical application.
Address Moscow State Pedagogical University, Department of Physics, 29 Malaya Pirogovskaya Street, Moscow 119435, Russia
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 1083-3668 ISBN Medium
Area Expedition Conference
Notes PMID:27626901 Approved no
Call Number Serial 1335
Permanent link to this record
 

 
Author Marksteiner, M.; Divochiy, A.; Sclafani, M.; Haslinger, P.; Ulbricht, H.; Korneev, A.; Semenov, A.; Gol'tsman, G.; Arndt, M.
Title A superconducting NbN detector for neutral nanoparticles Type Journal Article
Year 2009 Publication Nanotechnol. Abbreviated Journal Nanotechnol.
Volume (down) 20 Issue 45 Pages 455501
Keywords SSPD; SNSPD; *Electric Conductivity; Microscopy, Electron, Scanning; Nanoparticles/*chemistry/ultrastructure; Nanotechnology/*methods; *Photons
Abstract We present a proof-of-principle study of superconducting single photon detectors (SSPD) for the detection of individual neutral molecules/nanoparticles at low energies. The new detector is applied to characterize a laser desorption source for biomolecules and allows retrieval of the arrival time distribution of a pulsed molecular beam containing the amino acid tryptophan, the polypeptide gramicidin as well as insulin, myoglobin and hemoglobin. We discuss the experimental evidence that the detector is actually sensitive to isolated neutral particles.
Address University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria. markus.arndt@univie.ac.at
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 0957-4484 ISBN Medium
Area Expedition Conference
Notes PMID:19822928 Approved no
Call Number Serial 1239
Permanent link to this record
 

 
Author Gershenzon, E. M.; Gol'tsman, G. N.; Kagane, M. L.
Title Observation of free carrier resonances in p-type germanium at submillimeter wavelengths Type Journal Article
Year 1978 Publication Sov. Phys. Solid State Abbreviated Journal Sov. Phys. Solid State
Volume (down) 20 Issue 4 Pages 573-579
Keywords p-Ge, free carriers, resonances
Abstract The spectrum of hole resonances in pure p-Ge for submillimetre in quantizing magnetic fields has been studied and identified. Measurements of photoconductivity spectra of p-Ge were made in the wave range lambda = 2-0.3 mm at temp. of 4.2-15 deg K in magnetic fields H up to 40 Measurements at various frequencies showed that the position of a series of characteristic resonances depends on the frequency of the illumination. This is in line with theoretical conclusions about the effective mass of the carriers increasing with rise in the magnetic field as a result of the interaction of the edge of the valency band with the split spin-orbital interaction of the sub 7 exp + band and the conduction band. The relative intensity of the quantum resonance lines of the free holes depends on the excitation conditions.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1721
Permanent link to this record
 

 
Author Гершензон, Е. М.; Литвак-Горская, Л. Б.; Луговая, Г. Я.; Шапиро, Е. З.
Title Об интерпретации отрицательного магнитосопротивления в случае проводимости по верхней зоне Хаббарда в n-Ge⟨Sb⟩ Type Journal Article
Year 1986 Publication Физика и техника полупроводников Abbreviated Journal Физика и техника полупроводников
Volume (down) 20 Issue 1 Pages 99-103
Keywords n-Ge, Hubbard upper zone conductivity, negative magnetoresistance
Abstract В рамках теории квантовых поправок к проводимости объяснено отрицательное магнитосопротивление в n-Ge с концентрацией доноров Nd≃2.8⋅1016÷1.1⋅1017см−3, наблюдаемое в диапазоне температур 4.2−10 K, когда основной вклад в проводимость дают электроны верхней зоны Хаббарда. Показано, что время релаксации фазы волновой функции τφ определяется временем электрон-фононного взаимодействия τeph.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1759
Permanent link to this record
 

 
Author Matyushkin, Y.; Danilov, S.; Moskotin, M.; Belosevich, V.; Kaurova, N.; Rybin, M.; Obraztsova, E. D.; Fedorov, G.; Gorbenko, I.; Kachorovskii, V.; Ganichev, S.
Title Helicity-sensitive plasmonic terahertz interferometer Type Journal Article
Year 2020 Publication Nano Lett. Abbreviated Journal Nano Lett.
Volume (down) 20 Issue 10 Pages 7296-7303
Keywords graphene, plasmonic interferometer, radiation helicity, terahertz radiation
Abstract Plasmonic interferometry is a rapidly growing area of research with a huge potential for applications in the terahertz frequency range. In this Letter, we explore a plasmonic interferometer based on graphene field effect transistor connected to specially designed antennas. As a key result, we observe helicity- and phase-sensitive conversion of circularly polarized radiation into dc photovoltage caused by the plasmon-interference mechanism: two plasma waves, excited at the source and drain part of the transistor, interfere inside the channel. The helicity-sensitive phase shift between these waves is achieved by using an asymmetric antenna configuration. The dc signal changes sign with inversion of the helicity. A suggested plasmonic interferometer is capable of measuring the phase difference between two arbitrary phase-shifted optical signals. The observed effect opens a wide avenue for phase-sensitive probing of plasma wave excitations in two-dimensional materials.
Address CENTERA Laboratories, Institute of High Pressure Physics, PAS, 01-142 Warsaw, Poland
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 1530-6984 ISBN Medium
Area Expedition Conference
Notes PMID:32903004 Approved no
Call Number Serial 1781
Permanent link to this record
 

 
Author Ryabchun, Sergey; Tong, Cheuk-Yu Edward; Blundell, Raymond; Gol'tsman, Gregory
Title Stabilization scheme for hot-electron bolometer receivers using microwave radiation Type Journal Article
Year 2009 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume (down) 19 Issue 1 Pages 14-19
Keywords HEB, mixer, Allan variance, stabilization, radiometer equation
Abstract We present the results of a stabilization scheme for terahertz receivers based on NbN hot-electron bolometer (HEB) mixers that uses microwave radiation with a frequency much lower than the gap frequency of NbN to compensate for mixer current fluctuations. A feedback control loop, which actively controls the power level of the injected microwave radiation, has successfully been implemented to stabilize the operating point of the HEB mixer. This allows us to increase the receiver Allan time to 10 s and also improve the temperature resolution of the receiver by about 30% in the total power mode of operation.
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 1051-8223 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number RPLAB @ lobanovyury @ Serial 559
Permanent link to this record
 

 
Author Ryabchun, Sergey; Tong, Cheuk-Yu Edward; Paine, Scott; Lobanov, Yury; Blundell, Raymond; Goltsman, Gregory
Title Temperature resolution of an HEB receiver at 810 GHz Type Journal Article
Year 2009 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume (down) 19 Issue 3 Pages 293-296
Keywords HEB mixer
Abstract We present the results of direct measurements of the temperature resolution of an HEB receiver operating at 810 GHz, in both continuum and spectroscopic modes. In the continuum mode, the input of the receiver was switched between black bodies with different physical temperatures. With a system noise temperature of around 1100 K, the receiver was able to resolve loads which differed in temperature by about 1 K over an integration time of 5 seconds. This resolution is significantly worse than the value of 0.07 K given by the radiometer equation. In the spectroscopic mode, a gas cell filled with carbonyl sulphide (OCS) gas was used and the emission line at 813.3537060 GHz was measured using the receiver in conjunction with a digital spectrometer. From the observed spectra, we determined that the measurement uncertainty of the equivalent emission temperature was 2.8 K for an integration time of 0.25 seconds and a spectral resolution of 12 MHz, compared to a 1.4 K temperature resolution given by the radiometer equation. This relative improvement is due to the fact that at short integration times the contribution from 1/f noise and drift are less dominant. In both modes, the temperature resolution was improved by about 40% with the use of a feedback loop which adjusted the level of an injected microwave radiation to maintain a constant operating current of the HEB mixer. This stabilization scheme has proved to be very effective to keep the temperature resolution of the HEB receiver to close to the theoretical value given by the radiometer equation.
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 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 636
Permanent link to this record