|   | 
Details
   web
Records
Author Kitaygorsky, J.; Komissarov, I.; Jukna, A.; Pan, D.; Minaeva, O.; Kaurova, N.; Divochiy, A.; Korneev, A.; Tarkhov, M.; Voronov, B.; Milostnaya, I.; Gol'tsman, G.; Sobolewski, R.R.
Title Dark counts in nanostructured nbn superconducting single-photon detectors and bridges Type Journal Article
Year 2007 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 17 Issue 2 Pages 275-278
Keywords SSPD; SNSPD
Abstract We present our studies on dark counts, observed as transient voltage pulses, in current-biased NbN superconducting single-photon detectors (SSPDs), as well as in ultrathin (~4 nm), submicrometer-width (100 to 500 nm) NbN nanobridges. The duration of these spontaneous voltage pulses varied from 250 ps to 5 ns, depending on the device geometry, with the longest pulses observed in the large kinetic-inductance SSPD structures. Dark counts were measured while the devices were completely isolated (shielded by a metallic enclosure) from the outside world, in a temperature range between 1.5 and 6 K. Evidence shows that in our two-dimensional structures the dark counts are due to the depairing of vortex-antivortex pairs caused by the applied bias current. Our results shed some light on the vortex dynamics in 2D superconductors and, from the applied point of view, on intrinsic performance of nanostructured SSPDs.
Address
Corporate Author Thesis
Publisher Place of Publication (up) 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 Serial 1248
Permanent link to this record
 

 
Author Kitaygorsky, Jennifer; Komissarov, I.; Jukna, A.; Minaeva, O.; Kaurova, N.; Divochiy, A.; Korneev, A.; Tarkhov, M.; Voronov, B.; Milostnaya, I.; Gol'tsman, G.; Sobolewski, R.
Title Fluctuations in two-dimensional superconducting NbN nanobridges and nanostructures meanders Type Abstract
Year 2007 Publication Proc. APS March Meeting Abbreviated Journal Proc. APS March Meeting
Volume 52 Issue 1 Pages L9.00013
Keywords
Abstract We have observed fluctuations, manifested as sub-nanosecond to nanosecond transient, millivolt-amplitude voltage pulses, generated in two-dimensional NbN nanobridges, as well as in extended superconducting meander nanostructures, designed for single photon counting. Both nanobridges and nano-stripe meanders were biased at currents close to the critical current and measured in a range of temperatures from 1.5 to 8 K. During the tests, the devices were blocked from all incoming radiation by a metallic enclosure and shielded from any external magnetic fields. We attribute the observed spontaneous voltage pulses to the Kosterlitz-Thouless-type fluctuations, where the high enough applied bias current reduces the binding energy of vortex-antivortex pairs and, subsequently, thermal fluctuations break them apart causing the order parameter to momentarily reduce to zero, which in turn causes a transient voltage pulse. The duration of the voltage pulses depended on the device geometry (with the high-kinetic inductance meander structures having longer, nanosecond, pulses) while their rate was directly related to the biasing current as well as temperature.
Address
Corporate Author Thesis
Publisher Place of Publication (up) 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 1027
Permanent link to this record
 

 
Author Kitaygorsky, J.; Zhang, J.; Verevkin, A.; Sergeev, A.; Korneev, A.; Matvienko, V.; Kouminov, P.; Smirnov, K.; Voronov, B.; Gol'tsman, G.; Sobolewski, R.
Title Origin of dark counts in nanostructured NbN single-photon detectors Type Journal Article
Year 2005 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 15 Issue 2 Pages 545-548
Keywords SSPD dark counts, SNSPD, dark counts rate
Abstract We present our study of dark counts in ultrathin (3.5 to 10 nm thick), narrow (120 to 170 nm wide) NbN superconducting stripes of different lengths. In experiments, where the stripe was completely isolated from the outside world and kept at temperature below the critical temperature Tc, we detected subnanosecond electrical pulses associated with the spontaneous appearance of the temporal resistive state. The resistive state manifested itself as generation of phase-slip centers (PSCs) in our two-dimensional superconducting stripes. Our analysis shows that not far from Tc, PSCs have a thermally activated nature. At lowest temperatures, far below Tc, they are created by quantum fluctuations.
Address
Corporate Author Thesis
Publisher Place of Publication (up) 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 1057
Permanent link to this record
 

 
Author Zhang, Jin; Slysz, W.; Verevkin, A.; Okunev, O.; Chulkova, G.; Korneev, A.; Lipatov, A.; Gol'tsman, G. N.; Sobolewski, R.
Title Response time characterization of NbN superconducting single-photon detectors Type Journal Article
Year 2003 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal
Volume 13 Issue 2 Pages 180-183
Keywords SSPD jitter, SNSPD jitter
Abstract We report our time-resolved measurements of NbN-based superconducting single-photon detectors. The structures are meander-type, 10-nm thick, and 200-nm wide stripes and were operated at 4.2 K. We have shown that the NbN devices can count single-photon pulses with below 100-ps time resolution. The response signal pulse width was about 150 ps, and the system jitter was measured to be 35 ps.
Address
Corporate Author Thesis
Publisher IEEE Place of Publication (up) 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 1058
Permanent link to this record
 

 
Author Korneev, A.; Minaeva, O.; Divochiy, A.; Antipov, A.; Kaurova, N.; Seleznev, V.; Voronov, B.; Gol’tsman, G.; Pan, D.; Kitaygorsky, J.; Slysz, W.; Sobolewski, R.
Title Ultrafast and high quantum efficiency large-area superconducting single-photon detectors Type Conference Article
Year 2007 Publication Proc. SPIE Abbreviated Journal Proc. SPIE
Volume 6583 Issue Pages 65830I (1 to 9)
Keywords SSPD, SNSPD, superconducting NbN films, infrared single-photon detectors
Abstract We present our latest generation of superconducting single-photon detectors (SSPDs) patterned from 4-nm-thick NbN films, as meander-shaped  0.5-mm-long and  100-nm-wide stripes. The SSPDs exhibit excellent performance parameters in the visible-to-near-infrared radiation wavelengths: quantum efficiency (QE) of our best devices approaches a saturation level of  30% even at 4.2 K (limited by the NbN film optical absorption) and dark counts as low as 2x10-4 Hz. The presented SSPDs were designed to maintain the QE of large-active-area devices, but, unless our earlier SSPDs, hampered by a significant kinetic inductance and a nanosecond response time, they are characterized by a low inductance and GHz counting rates. We have designed, simulated, and tested the structures consisting of several, connected in parallel, meander sections, each having a resistor connected in series. Such new, multi-element geometry led to a significant decrease of the device kinetic inductance without the decrease of its active area and QE. The presented improvement in the SSPD performance makes our detectors most attractive for high-speed quantum communications and quantum cryptography applications.
Address
Corporate Author Thesis
Publisher Spie Place of Publication (up) Editor Dusek, M.; Hillery, M.S.; Schleich, W.P.; Prochazka, I.; Migdall, A.L.; Pauchard, A.
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 1249
Permanent link to this record