Wördenweber, R., Moshchalkov, V., Bending, S., & Tafuri, F. (Eds.). (2017). Superconductors at the nanoscale. From basic research to applications. Berlin/Boston: Walter de Gruyter GmbH.
|
Shcherbatenko, M., Lobanov, Y., Semenov, A., Kovalyuk, V., Korneev, A., Ozhegov, R., et al. (2017). Coherent detection of weak signals with superconducting nanowire single photon detector at the telecommunication wavelength. In I. Prochazka, R. Sobolewski, & R. B. James (Eds.), Proc. SPIE (Vol. 10229, 0G (1 to 12)). Spie.
Abstract: Achievement of the ultimate sensitivity along with a high spectral resolution is one of the frequently addressed problems, as the complication of the applied and fundamental scientific tasks being explored is growing up gradually. In our work, we have investigated performance of a superconducting nanowire photon-counting detector operating in the coherent mode for detection of weak signals at the telecommunication wavelength. Quantum-noise limited sensitivity of the detector was ensured by the nature of the photon-counting detection and restricted by the quantum efficiency of the detector only. Spectral resolution given by the heterodyne technique and was defined by the linewidth and stability of the Local Oscillator (LO). Response bandwidth was found to coincide with the detector’s pulse width, which, in turn, could be controlled by the nanowire length. In addition, the system noise bandwidth was shown to be governed by the electronics/lab equipment, and the detector noise bandwidth is predicted to depend on its jitter. As have been demonstrated, a very small amount of the LO power (of the order of a few picowatts down to hundreds of femtowatts) was required for sufficient detection of the test signal, and eventual optimization could lead to further reduction of the LO power required, which would perfectly suit for the foreseen development of receiver matrices and the need for detection of ultra-low signals at a level of less-than-one-photon per second.
|
Zhang, J., Verevkin, A., Slysz, W., Chulkova, G., Korneev, A., Lipatov, A., et al. (2017). Time-resolved characterization of NbN superconducting single-photon optical detectors. In J. C. Armitage (Ed.), Proc. SPIE (Vol. 10313, 103130F (1 to 3)). SPIE.
Abstract: NbN superconducting single-photon detectors (SSPDs) are very promising devices for their picosecond response time, high intrinsic quantum efficiency, and high signal-to-noise ratio within the radiation wavelength from ultraviolet to near infrared (0.4 gm to 3 gm) [1-3]. The single photon counting property of NbN SSPDs have been investigated thoroughly and a model of hotspot formation has been introduced to explain the physics of the photon- counting mechanism [4-6]. At high incident flux density (many-photon pulses), there are, of course, a large number of hotspots simultaneously formed in the superconducting stripe. If these hotspots overlap with each other across the width w of the stripe, a resistive barrier is formed instantly and a voltage signal can be generated. We assume here that the stripe thickness d is less than the electron diffusion length, so the hotspot region can be considered uniform. On the other hand, when the photon flux is so low that on average only one hotspot is formed across w at a given time, the formation of the resistive barrier will be realized only when the supercurrent at sidewalks surpasses the critical current (jr) of the superconducting stripe [1]. In the latter situation, the formation of the resistive barrier is associated with the phase-slip center (PSC) development. The effect of PSCs on the suppression of superconductivity in nanowires has been discussed very recently [8, 9] and is the subject of great interest.
|
Kahl, O., Ferrari, S., Kovalyuk, V., Vetter, A., Lewes-Malandrakis, G., Nebel, C., et al. (2017). Spectrally multiplexed single-photon detection with hybrid superconducting nanophotonic circuits: supplementary material. Osa.
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.
|
Korneev, A., Semenov, A., Vodolazov, D., Gol’tsman, G. N., & Sobolewski, R. (2017). Physics and operation of superconducting single-photon devices. In R. Wördenweber, V. Moshchalkov, S. Bending, & F. Tafuri (Eds.), Superconductors at the Nanoscale (pp. 279–308). De Gruyter.
|