Search

Your search keyword '"de Dood, M. J. A."' showing total 110 results
Start Over Author "de Dood, M. J. A."
110 results on '"de Dood, M. J. A."'

1. Probing the Hotspot Interaction Length in NbN Nanowire Superconducting Single-Photon Detectors

Author

Renema, J. J., Gaudio, R., Wang, Q., van Exter, M. P., Fiore, A., and de Dood, M. J. A.

Subjects
Condensed Matter - Superconductivity, Physics - Optics, Quantum Physics
Abstract

We measure the maximal distance at which two absorbed photons can jointly trigger a detection event in NbN nanowire superconducting single photon detector (SSPD) microbridges by comparing the one-photon and two-photon efficiency of bridges of different overall lengths, from 0 to 400 nm. We find a length of $23 \pm 2$ nm. This value is in good agreement with to size of the quasiparticle cloud at the time of the detection event.

Published
2016
Full Text
View/download PDF

2. Four-photon orbital angular momentum entanglement

Author

Hiesmayr, B. C., de Dood, M. J. A., and Löffler, W.

Subjects
Quantum Physics, Physics - Optics
Abstract

Quantum entanglement shared between more than two particles is essential to foundational questions in quantum mechanics, and upcoming quantum information technologies. So far, up to 14 two-dimensional qubits have been entangled, and an open question remains if one can also demonstrate entanglement of higher-dimensional discrete properties of more than two particles. A promising route is the use of the photon orbital angular momentum (OAM), which enables implementation of novel quantum information protocols, and the study of fundamentally new quantum states. To date, only two of such multidimensional particles have been entangled albeit with ever increasing dimensionality. Here we use pulsed spontaneous parametric downconversion (SPDC) to produce photon quadruplets that are entangled in their OAM, or transverse-mode degrees of freedom; and witness genuine multipartite Dicke-type entanglement. Apart from addressing foundational questions, this could find applications in quantum metrology, imaging, and secret sharing., Comment: 5 pages, 4 figures

Published
2015
Full Text
View/download PDF

3. The effect of magnetic field on the intrinsic detection efficiency of superconducting single-photon detectors

Author

Renema, J. J., Rengelink, R. J., Komen, I., Wang, Q., Gaudio, R., Hoog, K. P. M. op 't, Zhou, Z., Sahin, D., Fiore, A., Kes, P., Aarts, J., van Exter, M. P., de Dood, M. J. A., and Driessen, E. F. C.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Instrumentation and Detectors, Physics - Optics
Abstract

We experimentally investigate the effect of a magnetic field on photon detection in superconducting single-photon detectors. At low fields, the effect of a magnetic field is through the direct modification of the quasiparticle density of states of the superconductor, and magnetic field and bias current are interchangable, as is expected for homogeneous dirty-limit superconductors. At the field where a first vortex enters the detector, the effect of the magnetic field is reduced, up until the point where the critical current of the detector starts to be determined by flux flow. From this field on, increasing the magnetic field does not alter the detection of photons anymore, whereas it does still change the rate of dark counts. This result points at an intrinsic difference in dark and light counts, and also shows that no enhancement of the intrinsic detection efficiency of a straight SSPD wire is achievable in a magnetic field.

Published
2014
Full Text
View/download PDF

4. Complete experimental characterization of a superconducting multiphoton nanodetector

Author

Renema, J. J., Frucci, G., Zhou, Z., Mattioli, F., Gaggero, A., Leoni, R., de Dood, M. J. A., Fiore, A., and van Exter, M. P.

Subjects
Quantum Physics
Abstract

We present a complete method to characterize multiphoton detectors with a small overall detection efficiency. We do this by separating the nonlinear action of the multiphoton detection event from linear losses in the detector. Such a characterization is a necessary step for quantum information protocols with single and multiphoton detectors and can provide quantitative information to understand the underlying physics of a given detector. This characterization is applied to a superconducting multiphoton nanodetector, consisting of an NbN nanowire with a bowtie-shaped subwavelength constriction. Depending on the bias current, this detector has regimes with single and multiphoton sensitivity. We present the first full experimental characterization of such a detector.

Published
2011

5. Impedance model for the polarization-dependent optical absorption of superconducting single-photon detectors

Author

Driessen, E. F. C., Braakman, F. R., Reiger, E. M., Dorenbos, S. N., Zwiller, V., and de Dood, M. J. A.

Subjects
Physics - Optics, Physics - Instrumentation and Detectors
Abstract

We measured the single-photon detection efficiency of NbN superconducting single photon detectors as a function of the polarization state of the incident light for different wavelengths in the range from 488 nm to 1550 nm. The polarization contrast varies from ~5% at 488 nm to ~30% at 1550 nm, in good agreement with numerical calculations. We use an optical-impedance model to describe the absorption for polarization parallel to the wires of the detector. For lossy NbN films, the absorption can be kept constant by keeping the product of layer thickness and filling factor constant. As a consequence, we find that the maximum possible absorption is independent of filling factor. By illuminating the detector through the substrate, an absorption efficiency of ~70% can be reached for a detector on Si or GaAs, without the need for an optical cavity., Comment: 15 pages, 5 figures, submitted to Journal of Applied Physics

Published
2009
Full Text
View/download PDF

9. How noise affects quantum detector tomography.

Author

Wang, Q., Renema, J. J., Gaggero, A., Mattioli, F., Leoni, R., van Exter, M. P., and de Dood, M. J. A.

Subjects
NOISE, TOMOGRAPHY, PHOTON counting, NIOBIUM nitride, NANOWIRES, NOISE generators (Electronics)
Abstract

We determine the full photon number response of a NbN superconducting nanowire single photon detector via quantum detector tomography, and the results show the separation of linear, effective absorption efficiency from the internal detection efficiencies. In addition, we demonstrate an error budget for the complete quantum characterization of the detector. We find that for short times, the dominant noise source is shot noise, while laser power fluctuations limit the accuracy for longer timescales. The combined standard uncertainty of the internal detection efficiency derived from our measurements is about 2%. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

13. Amorphous silicon waveguides for microphotonics.

Author

de Dood, M. J. A., Polman, A., Zijlstra, T., and van der Drift, E. W. J. M.

Subjects
*AMORPHOUS semiconductors, *SILICON, *WAVEGUIDES, *IRRADIATION
Abstract

Amorphous silicon a-Si was made by ion irradiation of crystalline silicon with 1 × 10[sup 15] Xe ions cm[sup -2] at 77 K in the 1-4 MeV energy range. Thermal relaxation of the amorphous network at 500 °C for 1 h leads to an amorphous layer with a refractive index of n = 3.73, significantly higher than that of crystalline silicon (n = 3.45 at λ = 1.55 µm). a-Si can thus serve as a waveguide core in Si based optical waveguides. Channel waveguides were made by anisotropic etching of a 1.5 µm silicon-on-insulator structure that was partly amorphized. Transmission measurements of these waveguides as function of the amorphous silicon length show that the a-Si part of the waveguides exhibit a modal propagation loss of 70 cm[sup -1] (0.03 dB µm[sup -1]) and a bulk propagation loss of 115 cm[sup -1] (0.05 dB µm[sup -1]). Losses due to sidewall roughness are estimated, and are negligible compared to the modal loss. [ABSTRACT FROM AUTHOR]

Published
2002
Full Text
View/download PDF

14. Luminescence quantum efficiency and local optical density of states in thin film ruby made by ion implantation.

Author

Hensen, T. M., de Dood, M. J. A., and Polman, A.

Subjects
*LUMINESCENCE, *OPACITY (Optics), *THIN films, *RUBIES, *ION implantation
Abstract

Studies the luminescence quantum efficiency and local optical density of states in thin film ruby made by ion implantation. Peak concentrations; Increase in the luminescence intensity by annealing; Luminescence decay rate.

Published
2000
Full Text
View/download PDF

15. Design of NbN superconducting nanowire single-photon detectors with enhanced infrared detection efficiency

Author

Wang, Q, Renema, J J, Engel, A, de Dood, M J A, Wang, Q, Renema, J J, Engel, A, and de Dood, M J A

Abstract

We optimize the design of NbN nanowire superconducting single-photon detectors using the recently discovered position-dependent detection efficiency in these devices. This optimized design of meandering wire NbN detectors maximizes absorption at positions where photon detection is most efficient by altering the field distribution across the wire. In order to calculate the response of the detectors with different geometries, we use a monotonic local detection efficiency from a nanowire and optical absorption distribution via finite-difference-time-domain simulations. The calculations predict a trade-off between average absorption and absorption at the edge, leading to a predicted optimal wire width close to 100 nm for a 1550-nm wavelength, which drops to a 50-nm wire width for a 600-nm wavelength. The absorption at the edges can be enhanced by depositing a silicon nanowire on top of the superconducting nanowire, which improves both the total absorption efficiency and the internal detection efficiency of meandering wire structures. The proposed structure can be integrated in a relatively simple cavity structure to reach absorption efficiencies of 97% for perpendicular and 85% for parallel polarization.

Published
2017

21. Position-dependent local detection efficiency in a nanowire superconducting single-photon detector

Author

Renema, J J, Wang, Q, Gaudio, R, Komen, I, op 't Hoog, K, Sahin, D, Schilling, A, van Exter, M P, Fiore, A, Engel, A, de Dood, M J A, Renema, J J, Wang, Q, Gaudio, R, Komen, I, op 't Hoog, K, Sahin, D, Schilling, A, van Exter, M P, Fiore, A, Engel, A, and de Dood, M J A

Abstract

We probe the local detection efficiency in a nanowire superconducting single-photon detector along the cross-section of the wire with a far subwavelength resolution. We experimentally find a strong variation in the local detection efficiency of the device. We demonstrate that this effect explains previously observed variations in NbN detector efficiency as a function of device geometry.

Published
2015

23. The effect of magnetic field on the intrinsic detection efficiency of superconducting single-photon detectors

Author

Renema, J. J., primary, Rengelink, R. J., additional, Komen, I., additional, Wang, Q., additional, Gaudio, R., additional, op 't Hoog, K. P. M., additional, Zhou, Z., additional, Sahin, D., additional, Fiore, A., additional, Kes, P., additional, Aarts, J., additional, van Exter, M. P., additional, de Dood, M. J. A., additional, and Driessen, E. F. C., additional

Published
2015
Full Text
View/download PDF

24. Photoluminescence quantum efficiency of dense silicon nanocrystal ensembles in SiO2

Author

Walters, R. J., Kalkman, J., Polman, A., Atwater, H. A., and de Dood, M. J. A.

Subjects
Condensed Matter::Materials Science, Condensed Matter::Other, Physics::Optics, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Caltech Library Services
Abstract

The photoluminescence decay characteristics of silicon nanocrystals in dense ensembles fabricated by ion implantation into silicon dioxide are observed to vary in proportion to the calculated local density of optical states. A comparison of the experimental 1/e photoluminescence decay rates to the expected spontaneous emission rate modification yields values for the internal quantum efficiency and the intrinsic radiative decay rate of silicon nanocrystals. A photoluminescence quantum efficiency as high as 59%±9% is found for nanocrystals emitting at 750 nm at low excitation power. A power dependent nonradiative decay mechanism reduces the quantum efficiency at high pump intensity.

Published
2006

37. Index matching of surface plasmons

Author

de Dood, M. J. A., primary, Driessen, E. F. C., additional, Stolwijk, D., additional, van Exter, M. P., additional, Verschuuren, M. A., additional, and 't Hooft, G. W., additional

Published
2008
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results