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Comparison of multi-tensor diffusion models' performance for white matter integrity estimation in chronic stroke

Filatova, O.G. (author), van Vliet, L.J. (author), Schouten, A.C. (author), Kwakkel, Gert (author), van der Helm, F.C.T. (author), Vos, F.M. (author)

Better insight into white matter (WM) alterations after stroke onset could help to understand the underlying recovery mechanisms and improve future interventions. MR diffusion imaging enables to assess such changes. Our goal was to investigate the relation of WM diffusion characteristics derived from diffusion models of increasing complexity...

journal article 2018

document

Reversing Quantum Trajectories with Analog Feedback

De Lange, G. (author), Riste, D. (author), Tiggelman, M.J. (author), Eichler, C. (author), Tornberg, L. (author), Johansson, G. (author), Wallraff, A. (author), Schouten, R.N. (author), DiCarlo, L. (author)

We demonstrate the active suppression of transmon qubit dephasing induced by dispersive measurement, using parametric amplification and analog feedback. By real-time processing of the homodyne record, the feedback controller reverts the stochastic quantum phase kick imparted by the measurement on the qubit. The feedback operation matches a model...

journal article 2014

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Dynamic Beam Steering from a Subwavelength Slit by Selective Excitation of Guided Modes

Raghunathan, S.B. (author), Schouten, H.F. (author), Ubachs, W. (author), Ea Kim, B. (author), Gan, C.H. (author), Visser, T.D. (author)

Dynamic control of the direction of radiation of the light emanating from a subwavelength slit carved out of a thin metal film is experimentally demonstrated. This is achieved by selective excitation of the individual guided modes in the slit by setting the phase of three coherent laser beams. By changing the voltage across a piezoelement, we...

journal article 2013

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Millisecond charge-parity fluctuations and induced decoherence in a superconducting transmon qubit

Riste, D. (author), Bultink, C.C. (author), Tiggelman, M.J. (author), Schouten, R.N. (author), Lehnert, K.W. (author), DiCarlo, L. (author)

The tunnelling of quasiparticles across Josephson junctions in superconducting quantum circuits is an intrinsic decoherence mechanism for qubit degrees of freedom. Understanding the limits imposed by quasiparticle tunnelling on qubit relaxation and dephasing is of theoretical and experimental interest, particularly as improved understanding of...

journal article 2013

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Capacitive readout and gating of superconducting single photon detectors

Azzouz, H. (author), Heeres, R.W. (author), Dorenbos, S.N. (author), Schouten, R.N. (author), Zwiller, V. (author)

We propose and develop a readout scheme for superconducting single-photon detectors based on an integrated circuit, relaxing the need for large bandwidth amplification and resulting in voltage steps proportional to the number of detected photons. We also demonstrate time gating, to filter scattered light in time and reduce dark counts. This...

journal article 2013

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Printed circuit board metal powder filters for low electron temperatures

Mueller, F. (author), Schouten, R.N. (author), Brauns, M. (author), Gang, T. (author), Lim, W.H. (author), Lai, N.S. (author), Dzurak, A.S. (author), Van der Wiel, W.G. (author), Zwanenburg, F.A. (author)

We report the characterisation of printed circuit boards (PCB) metal powder filters and their influence on the effective electron temperature which is as low as 22 mK for a quantum dot in a silicon MOSFET structure in a dilution refrigerator. We investigate the attenuation behaviour (10 MHz–20 GHz) of filter made of four metal powders with a...

journal article 2013

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Modulated electron-multiplied fluorescence lifetime imaging microscope: All-solid-state camera for fluorescence lifetime imaging

Zhao, Q. (author), Schelen, B. (author), Schouten, R. (author)

We have built an all-solid-state camera that is directly modulated at the pixel level for frequency-domain fluorescence lifetime imaging microscopy (FLIM) measurements. This novel camera eliminates the need for an image intensifier through the use of an application-specific charge coupled device design in a frequency-domain FLIM system. The...

journal article 2012

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Read-out of superconducting single photon detectors

Dorenbos, S.N. (author), Zwiller, V.G. (author), Schouten, R.N. (author)

Detection arrangement having an array of at least one superconducting single photon detector (SSPD). The detection arrangement further has a cryogenic part (9) with the array of at least one SSPD (1), the cryogenic part (9) being at a superconducting temperature in operation. Also, a separate charge storage element (5) in the form of an...

patent 2011

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New Anaerobic, Ammonium-Oxidizing Community Enriched from Peat Soil

Hu, B.I. (author), Rush, D. (author), Van der Biezen, E. (author), Zheng, P. (author), Van Mullekom, M. (author), Schouten, S. (author), Sinninghe Damste, J.S. (author), Smolders, A.J.P. (author), Jetten, M.S.M. (author), Kartal, B. (author)

Anaerobic ammonium-oxidizing (anammox) bacteria have been recognized as an important sink for fixed nitrogen and are detected in many natural environments. However, their presence in terrestrial ecosystems has long been overlooked, and their contribution to the nitrogen cycling in natural and agricultural soils is currently unknown. Here we...

journal article 2010

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Quantum Nondemolition Measurement of a Superconducting Qubit in the Weakly Projective Regime

Picot, T. (author), Schouten, R. (author), Harmans, C.J.P.M. (author), Mooij, J.E. (author)

Quantum state detectors based on switching of hysteretic Josephson junctions biased close to their critical current are simple to use but have strong backaction. We show that the backaction of a dc-switching detector can be considerably reduced by limiting the switching voltage and using a fast cryogenic amplifier, such that a single readout can...

journal article 2010

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Low-crosstalk bifurcation detectors for coupled flux qubits

De Groot, P.C. (author), Van Loo, A.F. (author), Lisenfeld, J. (author), Schouten, R.N. (author), Lupa?cu, A. (author), Harmans, C.J.P.M. (author), Mooij, J.E. (author)

We present experimental results on the crosstalk between two ac-operated dispersive bifurcation detectors, implemented in a circuit for high-fidelity readout of two strongly coupled flux qubits. Both phase-dependent and phase-independent contributions to the crosstalk are analyzed. For proper tuning of the phase the measured crosstalk is 0.1%...

journal article 2010

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The intermuscular 3–7 Hz drive is not affected by distal proprioceptive input in myoclonus-dystonia

Van der Meer, J.N. (author), Schouten, A.C. (author), Bour, L.J. (author), De Vlugt, E. (author), Van Rootselaar, A.F. (author), Van der Helm, F.C.T. (author), Tijssen, M.A.J. (author)

In dystonia, both sensory malfunctioning and an abnormal intermuscular low-frequency drive of 3–7 Hz have been found, although cause and eVect are unknown. It is hypothesized that sensory processing is primarily disturbed and induces this drive. Accordingly, experimenter-controlled sensory input should be able to inXuence the frequency of the...

journal article 2010

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Tizanidine does not affect the linear relation of stretch duration to the long latency M2 response of m. flexor carpi radialis

Meskers, C.G.M. (author), Schouten, A.C. (author), Rich, M.M.L. (author), De Groot, J.H. (author), Schuurmans, J. (author), Arendzen, J.H. (author)

The long latency M2 electromyographic response of a suddenly stretched active muscle is stretch duration dependent of which the nature is unclear. We investigated the inXuence of the group II aVerent blocker tizanidine on M2 response characteristics of the m. Xexor carpi radialis (FCR). M2 response magnitude and eliciting probability in a group...

journal article 2009

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Josephson squelch filter for quantum nanocircuits

Forn-Díaz, P. (author), Schouten, R.N. (author), Den Braver, W.A. (author), Mooij, J.E. (author), Harmans, C.J.P.M. (author)

We fabricated and tested a squelch circuit consisting of a copper powder filter with an embedded Josephson junction connected to ground. For small signals (squelch ON), the small junction inductance attenuates strongly from dc to at least 1 GHz, while for higher frequencies dissipation in the copper powder increases the attenuation exponentially...

journal article 2009

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Diversity of Archaea and detection of crenarchaeotal amoA genes in the rivers Rhine and Têt

Herfort, L. (author), Kim, J.H. (author), Coolen, M.J.L. (author), Abbas, B. (author), Schouten, S. (author), Herndl, G.J. (author), Sinninghe Damste, J.S. (author)

Pelagic archaeal phylogenetic diversity and the potential for crenarchaeotal nitrification of Group 1.1a were determined in the rivers Rhine and Têt by 16S rRNA sequencing, catalyzed reported deposition-fluorescence in situ hybridization (CARD–FISH) and quantification of 16S rRNA and functional genes. Euryarchaeota were, for the first time,...

journal article 2009

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Design of Perturbation Signals for the Estimation of Proprioceptive Reflexes

Schouten, A.C. (author), De Vlugt, E. (author), Van der Helm, F.C.T. (author)

This study aimed to identify the functional contribution of reflexes to human motor control during posture maintenance. Continuous random force disturbances were applied at the hand while the subjects were instructed to minimize the deviation resulting from the force disturbances. The results were analyzed in the frequency domain with frequency...

journal article 2008

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Cryogenic amplifier for fast real-time detection of single-electron tunneling

Vink, I.T. (author), Nooitgedagt, T. (author), Schouten, R.N. (author), Vandersypen, L.M.K. (author), Wegscheider, W. (author)

The authors employ a cryogenic high electron mobility transistor (HEMT) amplifier to increase the bandwidth of a charge detection setup with a quantum point contact (QPC) charge sensor. The HEMT is operating at 1?K and the circuit has a bandwidth of 1?MHz. The noise contribution of the HEMT at high frequencies is only a few times higher than...

journal article 2007

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Identification of organic matter sources in sulfidic late Holocene Antarctic fjord sediments from fossil rDNA sequence analysis

Coolen, M.J.L. (author), Volkman, J.K. (author), Abbas, B. (author), Muyzer, G. (author), Schouten, S. (author), Sinninghe Damsté, J.S. (author)

The 18S ribosomal DNA (rDNA) isolated from sulfidic Holocene sediments and particulate organic matter in the water column of the stratified Small Meromictic Basin (SMB) in Ellis Fjord (eastern Antarctica) was analyzed to identify possible biological sources of organic matter. Previous work had shown that the sediments contained numerous diatom...

journal article 2007

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Low-frequency noise in Josephson junctions for superconducting qubits

Eroms, J. (author), Van Schaarenburg, L.C. (author), Driessen, E.F.C. (author), Plantenberg, J.H. (author), Huizinga, C.M. (author), Schouten, R.N. (author), Verbruggen, A.H. (author), Harmans, C.J.P.M. (author), Mooij, J.E. (author)

The authors have studied low-frequency resistance fluctuations in shadow-evaporated Al/AlOx/Al tunnel junctions. Between 300 and 5?K the spectral density follows a 1/f law. Below 5?K, individual defects distort the 1/f shape of the spectrum. The spectral density decreases linearly with temperature between 150 and 1?K and saturates below 0.8?K....

journal article 2006

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Real-time detection of single-electron tunneling using a quantum point contact

Vandersypen, L.M.K. (author), Elzerman, J.M. (author), Schouten, R.N. (author), Willems van Beveren, L.H. (author), Hanson, R. (author), Kouwenhoven, L.P. (author)

We observe individual tunnel events of a single electron between a quantum dot and a reservoir, using a nearby quantum point contact (QPC) as a charge meter. The QPC is capacitively coupled to the dot, and the QPC conductance changes by about 1% if the number of electrons on the dot changes by one. The QPC is voltage biased and the current is...

journal article 2004