225 citations · 540 across the 18 of their papers we have counts for
18 papers
Quantum Coherence in Superconducting Vortex States
Ameya Nambisan, Simon Günzler, Dennis Rieger +13
Abrikosov vortices, where the superconducting gap is completely suppressed in the core, are dissipative, semi-classical entities that impact applications from high-current-density…
On-chip stencil lithography for superconducting qubits
Roudy Hanna, Sören Ihssen, Simon Geisert +22
Improvements in circuit design and more recently in materials and surface cleaning have contributed to a rapid development of coherent superconducting qubits. However, organic resi…
High Impedance Granular Aluminum Ring Resonators
Mahya Khorramshahi, Martin Spiecker, Patrick Paluch +10
Superconducting inductors with impedance surpassing the resistance quantum, i.e., superinductors, are important for quantum technologies because they enable the development of prot…
Offset Charge Dependence of Measurement-Induced Transitions in Transmons
Mathieu Féchant, Marie Frédérique Dumas, Denis Bénâtre +9
A key challenge in achieving scalable fault tolerance in superconducting quantum processors is readout fidelity, which lags behind one- and two-qubit gate fidelity. A major limitat…
Low crosstalk modular flip-chip architecture for coupled superconducting qubits
Soeren Ihssen, Simon Geisert, Gabriel Jauma +10
We present a flip-chip architecture for an array of coupled superconducting qubits, in which circuit components reside inside individual microwave enclosures. In contrast to other…
Thermalization of a flexible microwave stripline measured by a superconducting qubit
Patrick Paluch, Martin Spiecker, Nicolas Gosling +6
With the demand for scalable cryogenic microwave circuitry continuously rising, recently developed flexible microwave striplines offer the tantalyzing perspective of increasing the…
Pure kinetic inductance coupling for cQED with flux qubits
Simon Geisert, Soeren Ihssen, Patrick Winkel +11
We demonstrate a qubit-readout architecture where the dispersive coupling is entirely mediated by a kinetic inductance. This allows us to engineer the dispersive shift of the reado…
Solomon equations for qubit and two-level systems: Insights into non-Poissonian quantum jumps
Martin Spiecker, Andrei I. Pavlov, Alexander Shnirman +1
We measure and model the combined relaxation of a qubit coupled to a discrete two-level system~(TLS) environment, also known as the central spin model. If the TLSs are much longer-…
Two-level system hyperpolarization using a quantum Szilard engine
Martin Spiecker, Patrick Paluch, Nicolas Gosling +16
The innate complexity of solid state physics exposes superconducting quantum circuits to interactions with uncontrolled degrees of freedom degrading their coherence. By using a sim…
Operating in a deep underground facility improves the locking of gradiometric fluxonium qubits at the sweet spots
Daria Gusenkova, Francesco Valenti, Martin Spiecker +14
We demonstrate flux-bias locking and operation of a gradiometric fluxonium artificial atom using two symmetric granular aluminum (grAl) loops to implement the superinductor. The gr…
Superconducting microwave magnetometer for absolute flux detection
Simon Günzler, Patrick Winkel, Dennis Rieger +5
Superconducting quantum interference devices (SQUIDs) are among the most sensitive detectors for out-of-plane magnetic field components. However, due to their periodic response wit…
Minimizing the discrimination time for quantum states of an artificial atom
Ivan Takmakov, Patrick Winkel, Farshad Foroughi +9
Fast discrimination between quantum states of superconducting artificial atoms is an important ingredient for quantum information processing. In circuit quantum electrodynamics, in…
Quantum non-demolition dispersive readout of a superconducting artificial atom using large photon numbers
Daria Gusenkova, Martin Spiecker, Richard Gebauer +13
Reading out the state of superconducting artificial atoms typically relies on dispersive coupling to a readout resonator. For a given system noise temperature, increasing the circu…
Superconducting granular aluminum resonators resilient to magnetic fields up to 1 Tesla
K. Borisov, D. Rieger, P. Winkel +8
High kinetic inductance materials constitute a valuable resource for superconducting quantum circuits and hybrid architectures. Superconducting granular aluminum (grAl) reaches kin…
State preparation of a fluxonium qubit with feedback from a custom FPGA-based platform
Richard Gebauer, Nick Karcher, Daria Gusenkova +12
We developed a versatile integrated control and readout instrument for experiments with superconducting quantum bits (qubits), based on a field-programmable gate array (FPGA) platf…
Implementation of a transmon qubit using superconducting granular aluminum
Patrick Winkel, Kiril Borisov, Lukas Grünhaupt +6
The high kinetic inductance offered by granular aluminum (grAl) has recently been employed for linear inductors in superconducting high-impedance qubits and kinetic inductance dete…
Transmon Qubit in a Magnetic Field: Evolution of Coherence and Transition Frequency
Andre Schneider, Tim Wolz, Marco Pfirrmann +4
We report on spectroscopic and time-domain measurements on a fixed-frequency concentric transmon qubit in an applied in-plane magnetic field to explore its limits of magnetic field…
Granular aluminum: A superconducting material for high impedance quantum circuits
Lukas Grünhaupt, Martin Spiecker, Daria Gusenkova +8
Superconducting quantum information processing machines are predominantly based on microwave circuits with relatively low characteristic impedance, of about 100 Ohm, and small anha…