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DESHIMA on ASTE: On-Sky Responsivity Calibration of the Integrated Superconducting Spectrometer

Baselmans, J.J.A. (author), Bosma, S. (author), Ikarashi, S. (author), Klapwijk, T.M. (author), Llombart, Nuria (author), Pascual Laguna, A. (author), Thoen, David (author), de Visser, P.J. (author), Yurduseven, O. (author), Endo, A. (author)

We are developing an ultra-wideband spectroscopic instrument, DESHIMA (DEep Spectroscopic HIgh-redshift MApper), based on the technologies of an on-chip filter bank and microwave kinetic inductance detector (MKID) to investigate dusty starburst galaxies in the distant universe at millimeter and submillimeter wavelengths. An on-site experiment of...

journal article 2020

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Wideband on-chip terahertz spectrometer based on a superconducting filterbank

Endo, A. (author), Karatsu, K. (author), Pascual Laguna, A. (author), Mirzaei, B. (author), Thoen, David (author), van Marrewijk, N.T. (author), Bosma, S. (author), Yurduseven, O. (author), Llombart, Nuria (author), Klapwijk, T.M. (author), Baselmans, J.J.A. (author)

Terahertz spectrometers with a wide instantaneous frequency coverage for passive remote sensing are enormously attractive for many terahertz applications, such as astronomy, atmospheric science, and security. Here we demonstrate a wide-band terahertz spectrometer based on a single superconducting chip. The chip consists of an antenna coupled...

journal article 2019

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First light demonstration of the integrated superconducting spectrometer

Endo, A. (author), Karatsu, K. (author), Bosma, S. (author), Ikarashi, S. (author), Klapwijk, T.M. (author), Llombart, Nuria (author), Pascual Laguna, A. (author), Thoen, David (author), de Visser, P.J. (author), Yurduseven, O. (author), Baselmans, J.J.A. (author)

Ultra-wideband, three-dimensional (3D) imaging spectrometry in the millimeter–submillimeter (mm–submm) band is an essential tool for uncovering the dust-enshrouded portion of the cosmic history of star formation and galaxy evolution^1–3. However, it is challenging to scale up conventional coherent heterodyne receivers⁴ or...

journal article 2019

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Reactive Magnetron Sputter Deposition of Superconducting Niobium Titanium Nitride Thin Films with Different Target Sizes

Bos, Boy Gustaaf Cornelis (author), Thoen, David (author), Haalebos, E. A.F. (author), Gimbel, P. M.L. (author), Klapwijk, T.M. (author), Baselmans, J.J.A. (author), Endo, A. (author)

The superconducting critical temperature (T-\mathrm{c} > 15 K) of niobium titanium nitride (NbTiN) thin films allows for low-loss circuits up to 1.1 THz, enabling on-chip spectroscopy and multipixel imaging with advanced detectors. The drive for large-scale detector microchips is demanding NbTiN films with uniform properties over an...

journal article 2017

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Superconducting Coplanar Waveguide Filters for Submillimeter Wave On-Chip Filterbank Spectrometers

Endo, A. (author), Yates, S.J.C. (author), Bueno, J. (author), Thoen, D.J. (author), Murugesan, V. (author), Baryshev, A.M. (author), Klapwijk, T.M. (author), Van der Werf, P.P. (author), Baselmans, J.J.A. (author)

We show the first experimental results which prove that superconducting NbTiN coplanar–waveguide resonators can achieve a loaded Q factor in excess of 800 in the 350 GHz band. These resonators can be used as narrow band pass filters for on-chip filter bank spectrometers for astronomy. Moreover, the low-loss coplanar waveguide technology provides...

journal article 2016

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The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

De Visser, P.J. (author), Yates, S.J.C. (author), Guruswamy, T. (author), Goldie, D.J. (author), Withington, S. (author), Neto, A. (author), Llombart, N. (author), Baryshev, A.M. (author), Klapwijk, T.M. (author), Baselmans, J.J.A. (author)

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 a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the gap edge of the superconductor. From there on,...

journal article 2015

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Fluctuations in the electron system of a superconductor exposed to a photon flux

De Visser, P.J. (author), Baselmans, J.J.A. (author), Bueno, J. (author), Llombart, N. (author), Klapwijk, T.M. (author)

In a superconductor, in which electrons are paired, the density of unpaired electrons should become zero when approaching zero temperature. Therefore, radiation detectors based on breaking of pairs promise supreme sensitivity, which we demonstrate using an aluminium superconducting microwave resonator. Here we show that the resonator also...

journal article 2014

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Evidence of a Nonequilibrium Distribution of Quasiparticles in the Microwave Response of a Superconducting Aluminum Resonator

De Visser, P.J. (author), Goldie, D.J. (author), Diener, P. (author), Withington, S. (author), Baselmans, J.J.A. (author), Klapwijk, T.M. (author)

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 nonequilibrium quasiparticle energy distribution. We have measured the electrodynamic response, quality factor, and resonant frequency of a superconducting aluminium microwave...

journal article 2014

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High optical efficiency and photon noise limited sensitivity of microwave kinetic inductance detectors using phase readout

Janssen, R.M.J. (author), Baselmans, J.J.A. (author), Endo, A. (author), Ferrari, L. (author), Yates, S.J.C. (author), Baryshev, A.M. (author), Klapwijk, T.M. (author)

We demonstrate photon noise limited performance in both phase and amplitude readout in microwave kinetic inductance detectors (MKIDs) consisting of NbTiN and Al, down to 100 fW of optical power. We simulate the far field beam pattern of the lens-antenna system used to couple radiation into the MKID and derive an aperture efficiency of 75%. This...

journal article 2013

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On-chip filter bank spectroscopy at 600–700?GHz using NbTiN superconducting resonators

Endo, A. (author), Sfiligoj, C. (author), Yates, S.J.C. (author), Baselmans, J.J.A. (author), Thoen, D.J. (author), Javadzadeh, S.M.H. (author), Van der Werf, P.P. (author), Baryshev, A.M. (author), Klapwijk, T.M. (author)

We experimentally demonstrate the principle of an on-chip submillimeter wave filter bank spectrometer, using superconducting microresonators as narrow band-separation filters. The filters are made of NbTiN/SiNx/NbTiN microstrip line resonators, which have a resonance frequency in the range of 614-685?GHz, two orders of magnitude higher in...

journal article 2013

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Microwave-induced excess quasiparticles in superconducting resonators measured through correlated conductivity fluctuations

De Visser, P.J. (author), Baselmans, J.J.A. (author), Yates, S.J.C. (author), Diener, P. (author), Endo, A. (author), Klapwijk, T.M. (author)

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 72 to 17??m?3 with a 6?dB decrease of the microwave power. The quasiparticle lifetime increases accordingly from 1.4 to 3.5?ms. These properties of the superconductor...

journal article 2012

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Design of an integrated filterbank for DESHIMA: On-chip submillimeter imaging spectrograph based on superconducting resonators

Endo, A. (author), Van der Werf, P. (author), Janssen, R.M.J. (author), De Visser, P.J. (author), Klapwijk, T.M. (author), Baselmans, J.J.A. (author), Ferrari, L. (author), Baryshev, A.M. (author), Yates, S.J.C. (author)

An integrated filterbank (IFB) in combination with microwave kinetic inductance detectors (MKIDs), both based on superconducting resonators, could be used to make broadband submillimeter imaging spectrographs that are compact and flexible. In order to investigate the possibility of adopting an IFB configuration for DESHIMA (Delft SRON High...

journal article 2012

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Generation-recombination noise: The fundamental sensitivity limit for kinetic inductance detectors

De Visser, P.J. (author), Baselmans, J.J.A. (author), Diener, P. (author), Yates, S.J.C. (author), Endo, A. (author), Klapwijk, T.M. (author)

We present measurements of quasiparticle generation-recombination noise in aluminium Microwave Kinetic Inductance Detectors, the fundamental noise source for these detectors. Both the quasiparticle lifetime and the number of quasiparticles can be determined from the noise spectra. The number of quasiparticles saturates to 10 ?m?3 at temperatures...

journal article 2012

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Power handling and responsivity of submicron wide superconducting coplanar waveguide resonators

Janssen, R.M.J. (author), Endo, A. (author), Baselmans, J.J.A. (author), De Visser, P.J. (author), Barends, R. (author), Klapwijk, T.M. (author)

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 requirements for space-based terahertz astronomy. Our aim is to investigate if this can be achieved by reducing the width of the CPW to much below what has typically been made...

journal article 2012

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Number Fluctuations of Sparse Quasiparticles in a Superconductor

De Visser, P.J. (author), Baselmans, J.J.A. (author), Diener, P. (author), Yates, S.J.C. (author), Endo, A. (author), Klapwijk, T.M. (author)

We have directly measured quasiparticle number fluctuations in a thin film superconducting Al resonator in thermal equilibrium. The spectrum of these fluctuations provides a measure of both the density and the lifetime of the quasiparticles. We observe that the quasiparticle density decreases exponentially with decreasing temperature, as...

journal article 2011

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Reduced frequency noise in superconducting resonators

Barends, R. (author), Vercruyssen, N. (author), Endo, A. (author), De Visser, P.J. (author), Zijlstra, T. (author), Klapwijk, T.M. (author), Baselmans, J.J.A. (author)

We report a reduction in the frequency noise in coplanar waveguide superconducting resonators. The reduction of 7 dB is achieved by removing the exposed dielectric substrate surface from the region with high electric fields and by using NbTiN. In a model-analysis the surface of NbTiN is found to be a negligible source of noise, experimentally...

journal article 2010

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Minimal resonator loss for circuit quantum electrodynamics

Barends, R. (author), Vercruyssen, N. (author), Endo, A. (author), De Visser, P.J. (author), Zijlstra, T. (author), Klapwijk, T.M. (author), Diener, P. (author), Yates, S.J.C. (author), Baselmans, J.J.A. (author)

We report quality factors of up to 500x10³ in superconducting resonators at the single photon levels needed for circuit quantum electrodynamics. This result is achieved by using NbTiN and removing the dielectric from regions with high electric fields. As demonstrated by a comparison with Ta, the crucial sources of intensity-dependent loss are...

journal article 2010

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Quasiparticle relaxation in high Q superconducting resonators

Barends, R. (author), Van Vliet, S. (author), Baselmans, J.J.A. (author), Yates, S.J.C. (author), Gao, J.R. (author), Klapwijk, T.M. (author)

We present measurements of the quasiparticle relaxation time in Ta superconducting films shaped as planar resonators using the response of the complex conductivity to photon flux. These films have been implanted with magnetic (Mn) as well as non-magnetic atoms (Al). We find a significant decrease of the relaxation time with increasing impurity...

conference paper 2009

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Noise in NbTiN, Al, and Ta Superconducting Resonators on Silicon and Sapphire Substrates

Barends, R. (author), Hortensius, H.L. (author), Zijlstra, T. (author), Baselmans, J.J.A. (author), Yates, S.J.C. (author), Gao, J.R. (author), Klapwijk, T.M. (author)

We present measurements of the frequency noise and resonance frequency temperature dependence in planar superconducting resonators on both silicon and sapphire substrates. We show, by covering the resonators with sputtered SiOx layers of different thicknesses, that the temperature dependence of the resonance frequency scales linearly with...

journal article 2009

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Enhancement of quasiparticle recombination in Ta and Al superconductors by implantation of magnetic and nonmagnetic atoms

Barends, R. (author), Van Vliet, S. (author), Baselmans, J.J.A. (author), Yates, S.J.C. (author), Gao, J.R. (author), Klapwijk, T.M. (author)

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 for different densities of magnetic and nonmagnetic atoms. For both Ta and Al, implanted with Mn, Ta, and Al, we observe an increase in the recombination rate. We...

journal article 2009