243 citations · 2.8k across the 88 of their papers we have counts for
16 papers · 1 filter
Volume dependence of microwave induced excess quasiparticles in superconducting resonators
Steven A. H. de Rooij, Jochem J. A. Baselmans, Juan Bueno +3
The presence of quasiparticles typically degrades the performance of superconducting microwave circuits. The readout signal can generate non-equilibrium quasiparticles, which lead…
Recombination of localized quasiparticles in disordered superconductors
Steven A. H. de Rooij, Remko Fermin, Kevin Kouwenhoven +6
Disordered superconductors offer new impedance regimes for quantum circuits, enable a pathway to protected qubits, and can improve superconducting detectors due to their high kinet…
Strong Reduction of Quasiparticle Fluctuations in a Superconductor due to Decoupling of the Quasiparticle Number and Lifetime
Steven A. H. de Rooij, Jochem J. A. Baselmans, Vignesh Murugesan +2
We measure temperature dependent quasiparticle fluctuations in a small Al volume, embedded in a NbTiN superconducting microwave resonator. The resonator design allows for read-out…
Reactive magnetron sputter deposition of superconducting niobium titanium nitride thin films with different target sizes
B. G. C. Bos, D. J. Thoen, E. A. F. Haalebos +4
The superconducting critical temperature (Tc > 15K) of niobium titanium nitride (NbTiN) thin films allows for low-loss circuits up to 1.1 THz, enabling on-chip spectroscopy and mul…
The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band
P. J. de Visser, S. J. C. Yates, T. Guruswamy +7
We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and…
Anomalous response of superconducting titanium nitride resonators to terahertz radiation
J. Bueno, P. C. J. J. Coumou, G. Zheng +5
We present an experimental study of KIDs fabricated of atomic layer deposited TiN films, and characterized at radiation frequencies of ~GHz. The responsivity to radiation is m…
Fluctuations in the electron system of a superconductor exposed to a photon flux
P. J. de Visser, J. J. A. Baselmans, J. Bueno +2
We report on fluctuations in the electron system, Cooper pairs and quasiparticles, of a superconducting aluminium film. The superconductor is exposed to pair-breaking photons (1.54…
Evidence of a nonequilibrium distribution of quasiparticles in the microwave response of a superconducting aluminium resonator
P. J. de Visser, D. J. Goldie, P. Diener +3
In a superconductor absorption of photons with an energy below the superconducting gap leads to redistribution of quasiparticles over energy and thus induces a strong non-equilibri…
Microwave properties of superconducting atomic-layer deposited TiN films
P. C. J. J. Coumou, M. R. Zuiddam, E. F. C. Driessen +3
We have grown superconducting TiN films by atomic layer deposition with thicknesses ranging from 6 to 89 nm. This deposition method allows us to tune the resistivity and critical t…
Homogeneous superconducting phase in TiN film : a complex impedance study
P. Diener, H. Schellevis, J. J. A. Baselmans
The low frequency complex impedance of a high resistivity 92 μΩ cm and 100 nm thick TiN superconducting film has been measured via the transmission of several high sensitivity GHz…
Power Handling and Responsivity of Submicron Wide Superconducting Coplanar Waveguide Resonators
R. M. J. Janssen, A. Endo, J. J. A. Baselmans +3
The sensitivity of microwave kinetic inductance detectors (MKIDs) based on coplanar waveguides (CPWs) needs to be improved by at least an order of magnitude to satisfy the requirem…
Microwave-induced excess quasiparticles in superconducting resonators measured through correlated conductivity fluctuations
P. J. de Visser, J. J. A. Baselmans, S. J. C. Yates +3
We have measured the number of quasiparticles and their lifetime in aluminium superconducting microwave resonators. The number of excess quasiparticles below 160 mK decreases from…
Number fluctuations of sparse quasiparticles in a superconductor
P. J. de Visser, J. J. A. Baselmans, P. Diener +3
We have directly measured quasiparticle number fluctuations in a thin film superconducting Al resonator in thermal equilibrium. The spectrum of these fluctuations provides a measur…
Enhancement of quasiparticle recombination in Ta and Al superconductors by implantation of magnetic and nonmagnetic atoms
R. Barends, S. van Vliet, J. J. A. Baselmans +3
The quasiparticle recombination time in superconducting films, consisting of the standard electron-phonon interaction and a yet to be identified low temperature process, is studied…
Quasiparticle relaxation in optically excited high-Q superconducting resonators
R. Barends, J. J. A. Baselmans, S. J. C. Yates +3
The quasiparticle relaxation time in superconducting films has been measured as a function of temperature using the response of the complex conductivity to photon flux. For tantalu…
Direct demonstration of circulating currents in a controllable -SQUID generated by a 0 to transition of the weak links
J. J. A. Baselmans, B. J. van Wees, T. M. Klapwijk
A controllable -SQUID is a DC SQUID with two controllable -junctions as weak links. A controllable -junction consists of a superconducting - normal metal - superconducting…