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| Author | Ferrari, S.; Kahl, O.; Kovalyuk, V.; Goltsman, G. N.; Korneev, A.; Pernice, W. H. P. | ||||
| Title | Waveguide-integrated single- and multi-photon detection at telecom wavelengths using superconducting nanowires | Type | Journal Article | ||
| Year | 2015 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
| Volume | 106 | Issue | 15 | Pages | 151101 (1 to 5) |
| Keywords | SSPD, SNSPD | ||||
| Abstract | We investigate single- and multi-photon detection regimes of superconducting nanowire detectors embedded in silicon nitride nanophotonic circuits. At near-infrared wavelengths, simultaneous detection of up to three photons is observed for 120 nm wide nanowires biased far from the critical current, while narrow nanowires below 100 nm provide efficient single photon detection. A theoretical model is proposed to determine the different detection regimes and to calculate the corresponding internal quantum efficiency. The predicted saturation of the internal quantum efficiency in the single photon regime agrees well with plateau behavior observed at high bias currents. W. H. P. Pernice acknowledges support by the DFG Grant Nos. PE 1832/1-1 and PE 1832/1-2 and the Helmholtz society through Grant No. HIRG-0005. The Ph.D. education of O. Kahl is embedded in the Karlsruhe School of Optics and Photonics (KSOP). G. N. Goltsman acknowledges support by Russian Federation President Grant HШ-1918.2014.2 and Ministry of Education and Science of the Russian Federation Contract No.: RFMEFI58614X0007. A. Korneev acknowledges support by Statement Task No. 3.1846.2014/k. V. Kovalyuk acknowledges support by Statement Task No. 2327. We also acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) and the State of Baden-Württemberg through the DFG-Center for Functional Nanostructures (CFN) within subproject A6.4. We thank S. Kühn and S. Diewald for the help with device fabrication as well as B. Voronov and A. Shishkin for help with NbN thin film deposition and A. Semenov for helpful discussion about the detection mechanism of nanowire SSPD's. The authors declare no competing financial interests. |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial  |
1211 | |||
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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 Volume | Series Issue | Edition | |||
| ISSN | 1094-4087 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:24104155 | Approved | no | ||
| Call Number | Serial |
1213 | |||
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| Author | Shangina, E. L.; Smirnov, K. V.; Morozov, D. V.; Kovalyuk, V. V.; Goltsman, G. N.; Verevkin, A. A.; Toropov, A. I.; Mauskopf, P. | ||||
| Title | Concentration dependence of energy relaxation time in AlGaAs/GaAs heterojunctions: direct measurements | Type | Journal Article | ||
| Year | 2011 | Publication | Semicond. Sci. Technol. | Abbreviated Journal | Semicond. Sci. Technol. |
| Volume | 26 | Issue | 2 | Pages | 025013 |
| Keywords | AlGaAs/GaAs heterojunctions | ||||
| Abstract | We present measurements of the energy relaxation time, τε, of electrons in a single heterojunction in a quasi-equilibrium state using microwave time-resolved spectroscopy at 4.2 K. We find the relaxation time has a power-law dependence on the carrier density of the two-dimensional electron gas, τε∝nγs with γ = 0.40 ± 0.02 for values of the carrier density, ns, from 1.6 × 1011 to 6.6 × 1011cm−2. The results are in good agreement with predictions taking into account the scattering of the carriers by both piezoelectric and deformation potential acoustic phonons. We compare these results with indirect measurements of the energy relaxation time from energy loss measurements involving Joule heating of the electron gas. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0268-1242 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial |
1215 | |||
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| Author | Kahl, O.; Ferrari, S.; Kovalyuk, V.; Vetter, A.; Lewes-Malandrakis, G.; Nebel, C.; Korneev, A.; Goltsman, G.; Pernice, W. | ||||
| Title | Spectrally multiplexed single-photon detection with hybrid superconducting nanophotonic circuits: supplementary material | Type | Miscellaneous | ||
| Year | 2017 | Publication | Optica | Abbreviated Journal | |
| Volume | Issue | Pages | 1-9 | ||
| Keywords | Quantum detectors; Spectrometers and spectroscopic instrumentation; Nanophotonics and photonic crystals; Fluorescence correlation spectroscopy; Fluorescence resonance energy transfer; Fluorescence spectroscopy; Imaging techniques; Optical components; Quantum key distribution | ||||
| Abstract | This document provides supplementary information to “Spectrally multiplexed single-photon detection with hybrid superconducting nanophotonic circuits", DOI:10.1364/optica.4.000557. Here we detail the on-chip spectrometer design, its characterization and the experimental setup we used. In addition, we present a detailed report concerning the characterization of the superconducting nanowire single photon detectors. In the final sections, we describe sample preparation and characterization of the nanodiamonds containing silicon vacancy color centers. | ||||
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| Publisher | Osa | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | Kahl:17 | Serial |
1218 | ||
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| Author | Goltsman, G. N.; Shcherbatenko, M. L.; Lobanov, Y. V.; Kovalyuk, V. V.; Kahl, O.; Ferrari, S.; Korneev, A.; Pernice, W. H. P. | ||||
| Title | Superconducting nanowire single photon detector for coherent detection of weak optical signals | Type | Abstract | ||
| Year | 2016 | Publication | LPHYS'16 | Abbreviated Journal | LPHYS'16 |
| Volume | Issue | Pages | 1-2 | ||
| Keywords | SSPD, SNSPD | ||||
| Abstract | Traditionally, photon detectors are operated in a direct detection mode counting incident photonswith a known quantum efficiency. This procedure allows one to detect weak sources of radiation but allthe information about its frequency is limited by the optical filtering/resonating structures used which arenot as precise as would be required for some practical applications. In this work we propose heterodynereceiver based on a photon counting mixer which would combine excellent sensitivity of a photon countingdetector and excellent spectral resolution given by the heterodyne technique. At present, Superconducting-Nanowire-Single-Photon-Detectors (SNSPDs) [1] are widely used in a variety of applications providing thebest possible combination of the sensitivity and speed. SNSPDs demonstrate lack of drawbacks like highdark count rate or autopulsing, which are common for traditional semiconductor-based photon detectors,such as avalanche photon diodes.In our study we have investigated SNSPD operated as a photon counting mixer. To fully understandits behavior in such a regime, we have utilized experimental setup based on a couple of distributedfeedback lasers irradiating at 1.5 micrometers, one of which is being the Local Oscillator (LO) and theother mimics the test signal [2]. The SNSPD was operated in the current mode and the bias currentwas slightly below of the critical current. Advantageously, we have found that LO power needed for anoptimal mixing is of the order of hundreds of femtowatts to a few picowatts, which is promising for manypractical applications, such as receiver matrices [3]. With use of the two lasers, one can observe thevoltage pulses produced by the detected photons, and the time distribution of the pulses reproduces thefrequency difference between the lasers, forming power response at the intermediate frequency which canbe captured by either an oscilloscope (an analysis of the pulse statistics is needed) or by an RF spectrumanalyzer. Photon-counting nature of the detector ensures quantum-limited sensitivity with respect to theoptical coupling achieved. In addition to the chip SNSPD with normal incidence coupling, we use thedetectors with a travelling wave geometry design [4]. In this case a NbN nanowire is placed on the topof a Si3N4 nanophotonic waveguide, thus increasing the efficient interaction length. For this reason it ispossible to achieve almost complete absorption of photons and reduce the detector footprint. This reducesthe noise of the device together with the expansion of the bandwidth. Integrated device scheme allowsus to measure the optical losses with high accuracy. Our approach is fully scalable and, along with alarge number of devices integrated on a single chip can be adapted to the mid and far IR ranges wherephoton-counting measurement may be beneficial as well [5].Acknowledgements: This work was supported in part by the Ministry of Education and Science of theRussian Federation, contract No. 14.B25.31.0007 and by RFBR grant No. 16-32-00465. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial |
1220 | |||
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