|   | 
Details
   web
Records
Author Morozov, P.; Lukina, M.; Shirmanova, M.; Divochiy, A.; Dudenkova, V.; Gol'tsman, G. N.; Becker, W.; Shcheslavskiy, V. I.
Title Singlet oxygen phosphorescence imaging by superconducting single-photon detector and time-correlated single-photon counting Type Journal Article
Year (down) 2021 Publication Opt. Lett. Abbreviated Journal Opt. Lett.
Volume 46 Issue 6 Pages 1217-1220
Keywords SSPD, SNSPD, applications
Abstract This Letter presents, to the best of our knowledge, a novel optical configuration for direct time-resolved measurements of luminescence from singlet oxygen, both in solutions and from cultured cells on photodynamic therapy. The system is based on the superconducting single-photon detector, coupled to the confocal scanner that is modified for the near-infrared measurements. The recording of a phosphorescence signal from singlet oxygen at 1270 nm has been done using time-correlated single-photon counting. The performance of the system is verified by measuring phosphorescence from singlet oxygen generated by the photosensitizers commonly used in photodynamic therapy: methylene blue and chlorin e6. The described system can be easily upgraded to the configuration when both phosphorescence from singlet oxygen and fluorescence from the cells can be detected in the imaging mode. Thus, co-localization of the signal from singlet oxygen with the areas inside the cells can be done.
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 0146-9592 ISBN Medium
Area Expedition Conference
Notes PMID:33720151 Approved no
Call Number Serial 1221
Permanent link to this record
 

 
Author Zolotov, P. I.; Semenov, A. V.; Divochiy, A. V.; Goltsman, G. N.; Romanov, N. R.; Klapwijk, T. M.
Title Dependence of photon detection efficiency on normal-state sheet resistance in marginally superconducting films of NbN Type Journal Article
Year (down) 2021 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 31 Issue 5 Pages 1-5
Keywords NbN SSPD, SNSPD
Abstract We present an extensive set of data on nanowire-type superconducting single-photon detectors based on niobium-nitride (NbN) to establish the empirical correlation between performance and the normal-state resistance per square. We focus, in particular, on the bias current, compared to the expected depairing current, needed to achieve a near-unity detection efficiency for photon detection. The data are discussed within the context of a model in which the photon energy triggers the movement of vortices i.e. superconducting dissipation, followed by thermal runaway. Since the model is based on the non-equilibrium theory for conventional superconductors deviations may occur, because the efficient regime is found when NbN acts as a marginal superconductor in which long-range phase coherence is frustrated.
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 Serial 1222
Permanent link to this record
 

 
Author Zolotov, P.; Semenov, A.; Divochiy, A.; Goltsman, G.
Title A comparison of VN and NbN thin films towards optimal SNSPD efficiency Type Journal Article
Year (down) 2021 Publication IEEE Trans. Appl. Supercond. Abbreviated Journal IEEE Trans. Appl. Supercond.
Volume 31 Issue 5 Pages 1-4
Keywords NbN SSPD, SNSPD, WSi
Abstract Based on early phenomenological ideas about the operation of superconducting single-photon detectors (SSPD or SNSPD), it was expected that materials with a lower superconducting gap should perform better in the IR range. The plausibility of this concept could be checked using two popular SSPD materials – NbN and WSi films. However, these materials differ strongly in crystallographic structure (polycrystalline B1 versus amorphous), which makes their dependence on disorder different. In our work we present a study of the single-photon response of SSPDs made from two disordered B1 structure superconductors – vanadium nitride and niobium nitride thin films. We compare the intrinsic efficiency of devices made from films with different sheet resistance values. While both materials have a polycrystalline structure and comparable diffusion coefficient values, VN films show metallic behavior over a wide range of sheet resistance, in contrast to NbN films with an insulator-like temperature dependence of resistivity, which may be partially due to enhanced Coulomb interaction, leading to different starting points for the normal electron density of states. The results show that even though VN devices are more promising in terms of theoretical predictions, their optimal performance was not reached due to lower values of sheet resistance.
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 Serial 1223
Permanent link to this record
 

 
Author Shcherbatenko, M.; Elezov, M.; Manova, N.; Sedykh, K.; Korneev, A.; Korneeva, Y.; Dryazgov, M.; Simonov, N.; Feimov, A.; Goltsman, G.; Sych, D.
Title Single-pixel camera with a large-area microstrip superconducting single photon detector on a multimode fiber Type Journal Article
Year (down) 2021 Publication Appl. Phys. Lett. Abbreviated Journal Appl. Phys. Lett.
Volume 118 Issue 18 Pages 181103
Keywords NbN SSPD, SNSPD
Abstract High sensitivity imaging at the level of single photons is an invaluable tool in many areas, ranging from microscopy to astronomy. However, development of single-photon sensitive detectors with high spatial resolution is very non-trivial. Here we employ the single-pixel imaging approach and demonstrate a proof-of-principle single-pixel single-photon imaging setup. We overcome the problem of low light gathering efficiency by developing a large-area microstrip superconducting single photon detector coupled to a multi-mode optical fiber interface. We show that the setup operates well in the visible and near infrared spectrum, and is able to capture images at the single-photon level.

We thank Philipp Zolotov and Pavel Morozov for NbN film fabrication, ARC coating, and fiber coupling of the detector. We also thank Swabian Instruments GmbH and Dr. Helmut Fedder personally for the kindly provided experimental equipment (Time Tagger Ultra 8). The work in the part of SNSPD research and development was supported by the Russian Foundation for Basic Research Project No. 18-29-20100. The work in the part of the optical setup and imaging was supported by Russian Foundation for Basic Research Project No. 20-32-51004.
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 0003-6951 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Serial 1770
Permanent link to this record
 

 
Author Korneev, A. A.
Title Superconducting NbN microstrip single-photon detectors Type Abstract
Year (down) 2021 Publication Proc. Quantum Optics and Photon Counting Abbreviated Journal Proc. Quantum Optics and Photon Counting
Volume 11771 Issue Pages
Keywords NbN SSPD, SNSPD
Abstract Superconducting Single-Photon Detectors (SSPD) invented two decades ago have evolved to a mature technology and have become devices of choice in the advanced applications of quantum optics, such as quantum cryptography and optical quantum computing. In these applications SSPDs are coupled to single-mode fibers and feature almost unity detection efficiency, negligible dark counts, picosecond timing jitter and MHz photon count rate. Meanwhile, there are great many applications requiring coupling to multi-mode fibers or free space. ‘Classical’ SSPDs with 100-nm-wide superconducting strip and covering area of about 100 µm2 are not suitable for further scaling due to degradation of performance and low fabrication yield. Recently we have demonstrated single-photon counting in micron-wide superconducting bridges and strips. Here we present our approach to the realization of practical photon-counting detectors of large enough area to be efficiently coupled to multi-mode fibers or free space. The detector is either a meander or a spiral of 1-µm-wide strip covering an area of 50x50 µm2. Being operated at 1.7K temperature it demonstrates the saturated detection efficiency (i.e. limited by the absorption in the detector) up to 1550 nm wavelength, about 10 ns dead time and timing jitter in range 50-100 ps.
Address
Corporate Author Thesis
Publisher SPIE Place of Publication Editor Prochazka, I.; Štefaňák, M.; Sobolewski, R.; Gábris, A.
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference Quantum Optics and Photon Counting; SPIE Optics + Optoelectronics, 2021, Online Only
Notes Approved no
Call Number Serial 1784
Permanent link to this record