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Author Sergeev, A. V.; Semenov, A. D.; Kouminov, P.; Trifonov, V.; Goghidze, I. G.; Karasik, B. S.; Gol’tsman, G. N.; Gershenzon, E. M.
Title Transparency of a YBa2Cu3O7-film/substrate interface for thermal phonons measured by means of voltage response to radiation Type Journal Article
Year 1994 Publication Phys. Rev. B Condens. Matter. Abbreviated Journal Phys. Rev. B Condens. Matter.
Volume 49 Issue 13 Pages 9091-9096
Keywords YBCO films
Abstract The transparency of a film/substrate interface for thermal phonons was investigated for YBa2Cu3O7 thin films deposited on MgO, Al2O3, LaAlO3, NdGaO3, and ZrO2 substrates. Both voltage response to pulsed-visible and to continuously modulated far-infrared radiation show two regimes of heat escape from the film to the substrate. That one dominated by the thermal boundary resistance at the film/substrate interface provides an initial exponential decay of the response. The other one prevailing at longer times or smaller modulation frequencies causes much slower decay and is governed by phonon diffusion in the substrate. The transparency of the boundary for phonons incident from the film on the substrate and also from the substrate on the film was determined separately from the characteristic time of the exponential decay and from the time at which one regime was changed to the other. Taking into account the specific heat of optical phonons and the temperature dependence of the group velocity of acoustic phonons, we show that the body of experimental data agrees with acoustic mismatch theory rather than with the model that assumes strong diffusive scattering of phonons at the interface.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829 ISBN Medium
Area Expedition Conference
Notes (up) PMID:10009690 Approved no
Call Number Serial 1648
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Author Nasr, M. B.; Minaeva, O.; Goltsman, G. N.; Sergienko, A. V.; Saleh, B. E.; Teich, M. C.
Title Submicron axial resolution in an ultrabroadband two-photon interferometer using superconducting single-photon detectors Type Journal Article
Year 2008 Publication Opt. Express Abbreviated Journal Opt. Express
Volume 16 Issue 19 Pages 15104-15108
Keywords SSPD, SNSPD
Abstract We generate ultrabroadband biphotons via the process of spontaneous parametric down-conversion in a quasi-phase-matched nonlinear grating that has a linearly chirped poling period. Using these biphotons in conjunction with superconducting single-photon detectors (SSPDs), we measure the narrowest Hong-Ou-Mandel dip to date in a two-photon interferometer, having a full width at half maximum (FWHM) of approximately 5.7 fsec. This FWHM corresponds to a quantum optical coherence tomography (QOCT) axial resolution of 0.85 µm. Our results indicate that a high flux of nonoverlapping biphotons may be generated, as required in many applications of nonclassical light.
Address Departments of Electrical & Computer Engineering and Physics, Quantum Imaging Laboratory, Boston University, Boston, MA 02215, USA. boshra@bu.edu
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 1094-4087 ISBN Medium
Area Expedition Conference
Notes (up) PMID:18795048 Approved no
Call Number Serial 1408
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Author Mohan, N.; Minaeva, O.; Gol'tsman, G. N.; Nasr, M. B.; Saleh, B. E.; Sergienko, A. V.; Teich, M. C.
Title Photon-counting optical coherence-domain reflectometry using superconducting single-photon detectors Type Journal Article
Year 2008 Publication Opt. Express Abbreviated Journal Opt. Express
Volume 16 Issue 22 Pages 18118-18130
Keywords SSPD, SNSPD
Abstract We consider the use of single-photon counting detectors in coherence-domain imaging. Detectors operated in this mode exhibit reduced noise, which leads to increased sensitivity for weak light sources and weakly reflecting samples. In particular, we experimentally demonstrate the possibility of using superconducting single-photon detectors (SSPDs) for optical coherence-domain reflectometry (OCDR). These detectors are sensitive over the full spectral range that is useful for carrying out such imaging in biological samples. With counting rates as high as 100 MHz, SSPDs also offer a high rate of data acquisition if the light flux is sufficient.
Address Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA. nm82@bu.edu
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 (up) PMID:18958090 Approved no
Call Number Serial 1407
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Author Rosfjord, Kristine M.; Yang, Joel K. W.; Dauler, Eric A.; Kerman, Andrew J.; Vikas Anant; Voronov, Boris M.; Gol'tsman, Gregory N.; Berggren, Karl K.
Title Nanowire Single-photon detector with an integrated optical cavity and anti-reflection coating Type Journal Article
Year 2006 Publication Opt. Express Abbreviated Journal Opt. Express
Volume 14 Issue 2 Pages 527-534
Keywords SSPD, SNSPD, cavity
Abstract We have fabricated and tested superconducting single-photon detectors and demonstrated detection efficiencies of 57% at 1550-nm wavelength and 67% at 1064 nm. In addition to the peak detection efficiency, a median detection efficiency of 47.7% was measured over 132 devices at 1550 nm. These measurements were made at 1.8K, with each device biased to 97.5% of its critical current. The high detection efficiencies resulted from the addition of an optical cavity and anti-reflection coating to a nanowire photodetector, creating an integrated nanoelectrophotonic device with enhanced performance relative to the original device. Here, the testing apparatus and the fabrication process are presented. The detection efficiency of devices before and after the addition of optical elements is also reported.
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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 (up) PMID:19503367 Approved no
Call Number Serial 388
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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.
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Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-9592 ISBN Medium
Area Expedition Conference
Notes (up) PMID:19802049 Approved no
Call Number Serial 1660
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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 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
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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 (up) PMID:19822928 Approved no
Call Number Serial 1239
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Author Sclafani, M.; Marksteiner, M.; Keir, F. M. L.; Divochiy, A.; Korneev, A.; Semenov, A.; Gol'tsman, G.; Arndt, M.
Title Sensitivity of a superconducting nanowire detector for single ions at low energy Type Journal Article
Year 2012 Publication Nanotechnol. Abbreviated Journal Nanotechnol.
Volume 23 Issue 6 Pages 065501 (1 to 5)
Keywords NbN SSPD, SNSPD, superconducting single ion detector, SSID, SNSID
Abstract We report on the characterization of a superconducting nanowire detector for ions at low kinetic energies. We measure the absolute single-particle detection efficiency eta and trace its increase with energy up to eta = 100%. We discuss the influence of noble gas adsorbates on the cryogenic surface and analyze their relevance for the detection of slow massive particles. We apply a recent model for the hot-spot formation to the incidence of atomic ions at energies between 0.2 and 1 keV. We suggest how the differences observed for photons and atoms or molecules can be related to the surface condition of the detector and we propose that the restoration of proper surface conditions may open a new avenue for SSPD-based optical spectroscopy on molecules and nanoparticles.
Address Vienna Center for Quantum Science and Technology, Faculty of Physics, University of Vienna, Vienna, Austria
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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 (up) PMID:22248823 Approved no
Call Number Serial 1380
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Author Pernice, W. H. P.; Schuck, C.; Minaeva, O.; Li, M.; Goltsman, G. N.; Sergienko, A. V.; Tang, H. X.
Title High-speed and high-efficiency travelling wave single-photon detectors embedded in nanophotonic circuits Type Journal Article
Year 2012 Publication Nat. Commun. Abbreviated Journal Nat. Commun.
Volume 3 Issue Pages 1325 (1 to 10)
Keywords waveguide SSPD
Abstract Ultrafast, high-efficiency single-photon detectors are among the most sought-after elements in modern quantum optics and quantum communication. However, imperfect modal matching and finite photon absorption rates have usually limited their maximum attainable detection efficiency. Here we demonstrate superconducting nanowire detectors atop nanophotonic waveguides, which enable a drastic increase of the absorption length for incoming photons. This allows us to achieve high on-chip single-photon detection efficiency up to 91% at telecom wavelengths, repeatable across several fabricated chips. We also observe remarkably low dark count rates without significant compromise of the on-chip detection efficiency. The detectors are fully embedded in scalable silicon photonic circuits and provide ultrashort timing jitter of 18 ps. Exploiting this high temporal resolution, we demonstrate ballistic photon transport in silicon ring resonators. Our direct implementation of a high-performance single-photon detector on chip overcomes a major barrier in integrated quantum photonics.
Address Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA
Corporate Author Thesis
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Medium
Area Expedition Conference
Notes (up) PMID:23271658; PMCID:PMC3535416 Approved no
Call Number Serial 1375
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Author Beck, M.; Rousseau, I.; Klammer, M.; Leiderer, P.; Mittendorff, M.; Winnerl, S.; Helm, M.; Gol'tsman, G.N.; Demsar, J.
Title Transient increase of the energy gap of superconducting NbN thin films excited by resonant narrow-band terahertz pulses Type Journal Article
Year 2013 Publication Phys. Rev. Lett. Abbreviated Journal Phys. Rev. Lett.
Volume 110 Issue 26 Pages 267003 (1 to 5)
Keywords NbN thin films, energy gap
Abstract Observations of radiation-enhanced superconductivity have thus far been limited to a few type-I superconductors (Al, Sn) excited at frequencies between the inelastic scattering rate and the superconducting gap frequency 2Delta/h. Utilizing intense, narrow-band, picosecond, terahertz pulses, tuned to just below and above 2Delta/h of a BCS superconductor NbN, we demonstrate that the superconducting gap can be transiently increased also in a type-II dirty-limit superconductor. The effect is particularly pronounced at higher temperatures and is attributed to radiation induced nonthermal electron distribution persisting on a 100 ps time scale.
Address Department of Physics and Center for Applied Photonics, University of Konstanz, D-78457, Germany
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes (up) PMID:23848912 Approved no
Call Number Serial 1370
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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 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.
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1094-4087 ISBN Medium
Area Expedition Conference
Notes (up) PMID:24104155 Approved no
Call Number Serial 1213
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Author Murphy, A.; Semenov, A.; Korneev, A.; Korneeva, Y.; Gol'tsman, G.; Bezryadin, A.
Title Three temperature regimes in superconducting photon detectors: quantum, thermal and multiple phase-slips as generators of dark counts Type Journal Article
Year 2015 Publication Sci. Rep. Abbreviated Journal Sci. Rep.
Volume 5 Issue Pages 10174 (1 to 10)
Keywords SPD, SSPD, SNSPD
Abstract We perform measurements of the switching current distributions of three w approximately 120 nm wide, 4 nm thick NbN superconducting strips which are used for single-photon detectors. These strips are much wider than the diameter of the vortex cores, so they are classified as quasi-two-dimensional (quasi-2D). We discover evidence of macroscopic quantum tunneling by observing the saturation of the standard deviation of the switching distributions at temperatures around 2 K. We analyze our results using the Kurkijarvi-Garg model and find that the escape temperature also saturates at low temperatures, confirming that at sufficiently low temperatures, macroscopic quantum tunneling is possible in quasi-2D strips and can contribute to dark counts observed in single photon detectors. At the highest temperatures the system enters a multiple phase-slip regime. In this range single phase-slips are unable to produce dark counts and the fluctuations in the switching current are reduced.
Address Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
Corporate Author Thesis
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Medium
Area Expedition Conference
Notes (up) PMID:25988591; PMCID:PMC4437302 Approved no
Call Number Serial 1344
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Author Kahl, O.; Ferrari, S.; Kovalyuk, V.; Goltsman, G. N.; Korneev, A.; Pernice, W. H. P.
Title Waveguide integrated superconducting single-photon detectors with high internal quantum efficiency at telecom wavelengths Type Journal Article
Year 2015 Publication Sci. Rep. Abbreviated Journal Sci. Rep.
Volume 5 Issue Pages 10941 (1 to 11)
Keywords optical waveguides; waveguide integrated SSPD; waveguide SSPD; nanophotonics
Abstract Superconducting nanowire single-photon detectors (SNSPDs) provide high efficiency for detecting individual photons while keeping dark counts and timing jitter minimal. Besides superior detection performance over a broad optical bandwidth, compatibility with an integrated optical platform is a crucial requirement for applications in emerging quantum photonic technologies. Here we present efficiencies close to unity at 1550nm wavelength. This allows for the SNSPDs to be operated at bias currents far below the critical current where unwanted dark count events reach milli-Hz levels while on-chip detection efficiencies above 70% are maintained. The measured dark count rates correspond to noiseequivalent powers in the 10–19W/Hz–1/2 range and the timing jitter is as low as 35ps. Our detectors are fully scalable and interface directly with waveguide-based optical platforms.
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Notes (up) PMID:26061283; PMCID:PMC4462017 Approved no
Call Number RPLAB @ kovalyuk @ Serial 946
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Author Yang, Y.; Fedorov, G.; Shafranjuk, S. E.; Klapwijk, T. M.; Cooper, B. K.; Lewis, R. M.; Lobb, C. J.; Barbara, P.
Title Electronic transport and possible superconductivity at Van Hove singularities in carbon nanotubes Type Journal Article
Year 2015 Publication Nano Lett. Abbreviated Journal Nano Lett.
Volume 15 Issue 12 Pages 7859-7866
Keywords carbon nanotubes, CNT, tunable superconductivity, van Hove singularities
Abstract Van Hove singularities (VHSs) are a hallmark of reduced dimensionality, leading to a divergent density of states in one and two dimensions and predictions of new electronic properties when the Fermi energy is close to these divergences. In carbon nanotubes, VHSs mark the onset of new subbands. They are elusive in standard electronic transport characterization measurements because they do not typically appear as notable features and therefore their effect on the nanotube conductance is largely unexplored. Here we report conductance measurements of carbon nanotubes where VHSs are clearly revealed by interference patterns of the electronic wave functions, showing both a sharp increase of quantum capacitance, and a sharp reduction of energy level spacing, consistent with an upsurge of density of states. At VHSs, we also measure an anomalous increase of conductance below a temperature of about 30 K. We argue that this transport feature is consistent with the formation of Cooper pairs in the nanotube.
Address Department of Physics, Georgetown University , Washington, District of Columbia 20057, United States
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Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Medium
Area Expedition Conference
Notes (up) PMID:26506109; Suuplementary info (attached to pdf) DOI: 10.1021/acs.nanolett.5b02564 Approved no
Call Number Serial 1782
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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 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
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Series Volume Series Issue Edition
ISSN 1083-3668 ISBN Medium
Area Expedition Conference
Notes (up) PMID:27626901 Approved no
Call Number Serial 1335
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Author Vetter, A.; Ferrari, S.; Rath, P.; Alaee, R.; Kahl, O.; Kovalyuk, V.; Diewald, S.; Goltsman, G. N.; Korneev, A.; Rockstuhl, C.; Pernice, W. H. P.
Title Cavity-enhanced and ultrafast superconducting single-photon detectors Type Journal Article
Year 2016 Publication Nano Lett. Abbreviated Journal Nano Lett.
Volume 16 Issue 11 Pages 7085-7092
Keywords SSPD; SNSPD; multiphoton detection; nanophotonic circuit; photonic crystal cavity
Abstract Ultrafast single-photon detectors with high efficiency are of utmost importance for many applications in the context of integrated quantum photonic circuits. Detectors based on superconductor nanowires attached to optical waveguides are particularly appealing for this purpose. However, their speed is limited because the required high absorption efficiency necessitates long nanowires deposited on top of the waveguide. This enhances the kinetic inductance and makes the detectors slow. Here, we solve this problem by aligning the nanowire, contrary to usual choice, perpendicular to the waveguide to realize devices with a length below 1 mum. By integrating the nanowire into a photonic crystal cavity, we recover high absorption efficiency, thus enhancing the detection efficiency by more than an order of magnitude. Our cavity enhanced superconducting nanowire detectors are fully embedded in silicon nanophotonic circuits and efficiently detect single photons at telecom wavelengths. The detectors possess subnanosecond decay ( approximately 120 ps) and recovery times ( approximately 510 ps) and thus show potential for GHz count rates at low timing jitter ( approximately 32 ps). The small absorption volume allows efficient threshold multiphoton detection.
Address Institute of Physics, University of Munster , 48149 Munster, Germany
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 1530-6984 ISBN Medium
Area Expedition Conference
Notes (up) PMID:27759401 Approved no
Call Number Serial 1208
Permanent link to this record