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| Author | Sidorova, M.; Semenov, A.; Hübers, H.-W.; Kuzmin, A.; Doerner, S.; Ilin, K.; Siegel, M.; Charaev, I.; Vodolazov, D. | ||||
| Title | Timing jitter in photon detection by straight superconducting nanowires: Effect of magnetic field and photon flux | Type | Journal Article | ||
| Year | 2018 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
| Volume | 98 | Issue | 13 | Pages | 134504 (1 to 14) |
| Keywords | SNSPD, NbN namowires | ||||
| Abstract | We studied the effects of the external magnetic field and photon flux on timing jitter in photon detection by straight superconducting NbN nanowires. At two wavelengths 800 and 1560 nm, statistical distribution in the appearance times of photon counts exhibits Gaussian shape at small times and an exponential tail at large times. The characteristic exponential time is larger for photons with smaller energy and increases with external magnetic field while variations in the Gaussian part of the distribution are less pronounced. Increasing photon flux drives the nanowire from the discrete quantum detection regime to the uniform bolometric regime that averages out fluctuations of the total number of nonequilibrium electrons created by the photon and drastically reduces jitter. The difference between standard deviations of Gaussian parts of distributions for these two regimes provides the measure for the strength of electron-number fluctuations; it increases with the photon energy. We show that the two-dimensional hot-spot detection model explains qualitatively the effect of magnetic field. | ||||
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ISSN  |
2469-9950 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1842 | |||
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| Author | Shcherbatenko, M. L.; Elezov, M. S.; Goltsman, G. N.; Sych, D. V. | ||||
| Title | Sub-shot-noise-limited fiber-optic quantum receiver | Type | Journal Article | ||
| Year | 2020 | Publication | Phys. Rev. A | Abbreviated Journal | Phys. Rev. A |
| Volume | 101 | Issue | 3 | Pages | 032306 (1 to 5) |
| Keywords | SSPD mixer, SNSPD | ||||
| Abstract | We experimentally demonstrate a quantum receiver based on the Kennedy scheme for discrimination between two phase-modulated weak coherent states. The receiver is assembled entirely from standard fiber-optic elements and operates at a conventional telecom wavelength of 1.55 μm. The local oscillator and the signal are transmitted through different optical fibers, and the displaced signal is measured with a high-efficiency superconducting nanowire single-photon detector. We show the discrimination error rate is two times below that of a shot-noise-limited receiver with the same system detection efficiency. | ||||
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| ISSN |
2469-9926 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1268 | |||
| Permanent link to this record | |||||
| Author | Pyatkov, Felix; Khasminskaya, Svetlana; Fütterling, Valentin; Fechner, Randy; Słowik, Karolina; Ferrari, Simone; Kahl1, Oliver; Kovalyuk, Vadim; Rath, Patrik; Vetter, Andreas; Flavel, Benjamin S.; Hennrich, Frank; Kappes, Manfred M.; Gol’tsman, Gregory N.; Korneev, Alexander; Rockstuhl, Carsten; Krupke, Ralph; Pernice, Wolfram H. P. | ||||
| Title | Carbon nanotubes as exceptional electrically driven on-chip light sources | Type | Miscellaneous | ||
| Year | 2016 | Publication | 2Physics | Abbreviated Journal | 2Physics |
| Volume | Issue | Pages | |||
| Keywords | carbon nanotubes, CNT | ||||
| Abstract | Carbon nanotubes (CNTs) belong to the most exciting objects of the nanoworld. Typically, around 1 nm in diameter and several microns long, these cylindrically shaped carbon-based structures exhibit a number of exceptional mechanical, electrical and optical characteristics [1]. In particular, they are promising ultra-small light sources for the next generation of optoelectronic devices, where electrical components are interconnected with photonic circuits. Few years ago, we demonstrated that electically driven CNTs can serve as waveguide-integrated light sources [2]. Progress in the field of nanotube sorting, dielectrophoretical site-selective deposition and efficient light coupling into underlying substrate has made CNTs suitable for wafer-scale fabrication of active hybrid nanophotonic devices [2,3]. Recently we presented a nanotube-based waveguide integrated light emitters with tailored, exceptionally narrow emission-linewidths and short response times [4]. This allows conversion of electrical signals into well-defined optical signals directly within an optical waveguide, as required for future on-chip optical communication. Schematics and realization of this device is shown in Figure 1. The devices were manufactured by etching a photonic crystal waveguide into a dielectric layer following electron beam lithography. Photonic crystals are nanostructures that are also used by butterflies to give the impression of color on their wings. The same principle has been used in this study to select the color of light emitted by the CNT. The precise dimensions of the structure were numerically simulated to tailor the properties of the final device. Metallic contacts in the vicinity to the waveguide were fabricated to provide electrical access to CNT emitters. Finally, CNTs, sorted by structural and electronic properties, were deposited from a solution across the waveguide using dielectrophoresis, which is an electric-field-assisted deposition technique. |
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| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN |
2372-1782 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1219 | |||
| Permanent link to this record | |||||
| Author | Saveskul, N. A.; Titova, N. A.; Baeva, E. M.; Semenov, A. V.; Lubenchenko, A. V.; Saha, S.; Reddy, H.; Bogdanov, S. I.; Marinero, E. E.; Shalaev, V. M.; Boltasseva, A.; Khrapai, V. S.; Kardakova, A. I.; Goltsman, G. N. | ||||
| Title | Superconductivity behavior in epitaxial TiN films points to surface magnetic disorder | Type | Journal Article | ||
| Year | 2019 | Publication | Phys. Rev. Applied | Abbreviated Journal | Phys. Rev. Applied |
| Volume | 12 | Issue | 5 | Pages | 054001 |
| Keywords | epitaxial TiN films | ||||
| Abstract | We analyze the evolution of the normal and superconducting properties of epitaxial TiN films, characterized by high Ioffe-Regel parameter values, as a function of the film thickness. As the film thickness decreases, we observe an increase of the residual resistivity, that becomes dominated by diffusive surface scattering for d≤20nm. At the same time, a substantial thickness-dependent reduction of the superconducting critical temperature is observed compared to the bulk TiN value. In such high-quality material films, this effect can be explained by a weak magnetic disorder residing in the surface layer with a characteristic magnetic defect density of approximately 1012cm−2. Our results suggest that surface magnetic disorder is generally present in oxidized TiN films. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2331-7019 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1166 | |||
| Permanent link to this record | |||||
| Author | Baeva, E. M.; Sidorova, M. V.; Korneev, A. A.; Smirnov, K. V.; Divochy, A. V.; Morozov, P. V.; Zolotov, P. I.; Vakhtomin, Y. B.; Semenov, A. V.; Klapwijk, T. M.; Khrapai, V. S.; Goltsman, G. N. | ||||
| Title | Thermal properties of NbN single-photon detectors | Type | Journal Article | ||
| Year | 2018 | Publication | Phys. Rev. Applied | Abbreviated Journal | Phys. Rev. Applied |
| Volume | 10 | Issue | 6 | Pages | 064063 (1 to 8) |
| Keywords | NbN SSPD, SNSPD | ||||
| Abstract | We investigate thermal properties of a NbN single-photon detector capable of unit internal detection efficiency. Using an independent calibration of the coupling losses, we determine the absolute optical power absorbed by the NbN film and, via resistive superconductor thermometry, the temperature dependence of the thermal resistance Z(T) of the NbN film. In principle, this approach permits simultaneous measurement of the electron-phonon and phonon-escape contributions to the energy relaxation, which in our case is ambiguous because of the similar temperature dependencies. We analyze Z(T) with a two-temperature model and impose an upper bound on the ratio of electron and phonon heat capacities in NbN, which is surprisingly close to a recent theoretical lower bound for the same quantity in similar devices. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2331-7019 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1226 | |||
| Permanent link to this record | |||||