153 citations · 745 across the 23 of their papers we have counts for
23 papers
Spatial homogeneity of superconducting order parameter in NbN films grown by atomic layer deposition
J. Lorenz, S. Linzen, M. Ziegler +5
Due to their high kinetic inductance, highly disordered superconducting thin films are a potential hardware for the realization of compact, low-noise elements in cryoelectronic app…
Basic cell for a quantum microwave router
Evgeniya Mutsenik, Aidar Sultanov, Leonie Kaczmarek +4
We report the first experimental realization of a scalable basic cell for quantum routing, enabling coherent control and exchange of microwave photons between two spatially separat…
Measuring coherent dynamics of a superconducting qubit in an open waveguide
Aidar Sultanov, Evgeniya Mutsenik, Matthias Schmelz +5
We measured the relaxation and decoherence rates of a superconducting transmon qubit in a resonator-free setting. In our experiments, the qubit is coupled to an open coplanar waveg…
Optically pumped vector magnetometer using a strong bias magnetic field
Thomas Schönau, Theo Scholtes, Florian Wittkämper +4
We present a novel approach allowing an optically pumped magnetometer (OPM) to be operated within Earth's magnetic field as a vector magnetometer whose sensitive axis can be freely…
Stepping closer to pulsed single microwave photon detectors for axions search
A. D'Elia, A. Rettaroli, S. Tocci +23
Axions detection requires the ultimate sensitivity down to the single photon limit. In the microwave region this corresponds to energies in the yJ range. This extreme sensitivity h…
Reflection-enhanced gain in traveling-wave parametric amplifiers
S. Kern, P. Neilinger, E. Iľichev +12
The operating principle of traveling-wave parametric amplifiers is typically understood in terms of the standard coupled mode theory, which describes the evolution of forward propa…
Integrated optically pumped magnetometer for measurements within Earth's magnetic field
G. Oelsner, R. IJsselsteijn, T. Scholtes +7
We present a portable optically pumped magnetometer instrument for ultra-sensitive measurements within the Earth's magnetic field. The central part of the system is a sensor head o…
Performance analysis of an optically pumped magnetometer in Earth's magnetic field
G. Oelsner, V. Schultze, R. IJsselsteijn +1
We experimentally investigate the influence of the orientation of optically pumped magnetometers in Earth's magnetic field. We focus our analysis to an operational mode that promis…
Controlling the energy gap of a tunable two-level system by ac drive
G. Oelsner, U. Hübner, E. Il'ichev
We study the influence of a strong off-resonant driving signal to the energy levels of a superconducting flux qubit both experimentally and theoretically. In the experiment, we car…
Sources of heading error in optically pumped magnetometers operated at Earth's magnetic field
G. Oelsner, V. Schultze, R. IJsselsteijn +2
When optically pumped magnetometers are aimed for the use in Earth's magnetic field, the orientation of the sensor to the field direction is of special importance to achieve accura…
Detection of weak microwave fields with an underdamped Josephson junction
G. Oelsner, C. K. Andersen, M. Rehák +6
We have constructed a microwave detector based on the voltage switching of an underdamped Josephson junction, that is positioned at a current antinode of a λ/4 coplanar waveguide r…
Landau-Zener-Stückelberg-Majorana lasing in circuit QED
P. Neilinger, S. N. Shevchenko, J. Bogár +7
We demonstrate amplification (and attenuation) of a probe signal by a driven two-level quantum system in the Landau-Zener-Stückelberg-Majorana regime by means of an experiment, in…
Signal amplification in a qubit-resonator system
D. S. Karpov, G. Oelsner, S. N. Shevchenko +2
We study the dynamics of a qubit-resonator system, when the resonator is driven by two signals. The interaction of the qubit with the high-amplitude driving we consider in terms of…
Experimental system design for the integration of trapped-ion and superconducting qubit systems
D. De Motte, A. R. Grounds, M. Rehák +8
We present a design for the experimental integration of ion trapping and superconducting qubit systems as a step towards the realization of a quantum hybrid system. The scheme addr…
Two-photon lasing by a superconducting qubit
P. Neilinger, M. Rehák, M. Grajcar +3
We study the response of a magnetic-field-driven superconducting qubit strongly coupled to a superconducting coplanar waveguide resonator. We observed a strong amplification/dampin…
Resonance at the Rabi frequency in a superconducting flux qubit
Ya. S. Greenberg, E. Il'ichev, G. Oelsner +1
We analyze a system composed of a superconducting flux qubit coupled to a transmission-line resonator driven by two signals with frequencies close to the resonator's harmonics. The…
Parametric amplification by coupled flux qubits
M. Rehak, P. Neilinger, M. Grajcar +4
We report the parametric amplification of a microwave signal in a Kerr medium formed from superconducting qubits. Two mutually coupled flux qubits, embedded in the current antinode…
Quantized resonator field coupled to a current-biased Josephson junction in circuit QED
Christian Kraglund Andersen, Gregor Oelsner, Evgeni Il'ichev +1
A Lagrangian formalism is used to derive the Hamiltonian for a /4 resonator shunted by a current-biased Josephson junction. The eigenstates and the quantum dynamics of the syste…
Implementation of a Quantum Metamaterial
Pascal Macha, Gregor Oelsner, Jan-Michael Reiner +7
Manipulating the propagation of electromagnetic waves through sub-wavelength sized artificial structures is the core function of metamaterials. Resonant structures, such as split r…
Amplification and attenuation of a probe signal by doubly-dressed states
S. N. Shevchenko, G. Oelsner, Ya. S. Greenberg +6
We analyse a system composed of a qubit coupled to electromagnetic fields of two high quality quantum oscillators. Particular realization of such a system is the superconducting qu…
Dressed-state amplification by a superconducting qubit
G. Oelsner, P. Macha, O. V. Astafiev +6
We demonstrate amplification of a microwave signal by a strongly driven two-level system in a coplanar waveguide resonator. The effect known from optics as dressed-state lasing is…
Losses in coplanar waveguide resonators at millikelvin temperatures
P. Macha, S. H. W. van der Ploeg, G. Oelsner +4
We study the loss rate for a set of lambda/2 coplanar waveguide resonators at millikelvin temperatures (20 mK - 900mK) and different applied powers (3E-19 W - 1E-12 W). The loss ra…
Weak continuous monitoring of a flux qubit using coplanar waveguide resonator
G. Oelsner, S. H. W. van der Ploeg, P. Macha +9
We study a flux qubit in a coplanar waveguide resonator by measuring transmission through the system. In our system with the flux qubit decoupled galvanically from the resonator, t…