University of Stuttgart

Waveguide-integrated colour centres in silicon carbide with broadband photonic crystal reflectors for efficient readout

Marcel Krumrein, Julian M. Bopp, Timo Steidl +5

Spin-active colour centres in 4H silicon carbide are promising candidates as building blocks for quantum information applications. To increase the photon count rate of the emitters…

Multiqubit Rydberg Gates for Quantum Error Correction

David F. Locher, Josias Old, Katharina Brechtelsbauer +4

Multiqubit gates that involve three or more qubits are usually thought to be of little significance for fault-tolerant quantum error correction because single gate faults can lead…

Optimizing magnetic coupling in lumped element superconducting resonators for molecular spin qubits

Marcos Rubín-Osanz, David Rodriguez, Ignacio Gimeno +18

We engineer lumped-element superconducting resonators that maximize magnetic coupling to molecular spin qubits, achieving record single-spin couplings up to $100$ kHz and collectiv…

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…

Readout of a solid state spin ensemble at the projection noise limit

Rouven Maier, Cheng-I Ho, Andrej Denisenko +4

Spin ensembles are central to quantum science, from frequency standards and fundamental physics searches to magnetic resonance spectroscopy and quantum sensing. Their performance i…

Steady-state dynamics of quantum frequency combs in microring resonators

Patrick Tritschler, Torsten Ohms, André Zimmermann +1

Optical frequency combs are utilized in a wide range of optical applications, including atomic clocks, interferometers, and various sensing technologies. They are often generated v…

Steady-state entanglement of spin qubits mediated by nonreciprocal and chiral magnons

Martijn Dols, Mikhail Cherkasskii, Victor A. S. V. Bittencourt +3

We propose a hybrid quantum system in which a magnet supporting non-reciprocal magnons, chiral magnons, or both mediates the dissipative and unidirectional coupling of spin qubits.…

Data-Efficient Quantum Noise Modeling via Machine Learning

Yanjun Ji, Marco Roth, David A. Kreplin +2

Maximizing the computational utility of near-term quantum processors requires predictive noise models that inform robust, noise-aware compilation and error mitigation. Conventional…

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…

Ultrastable, low-error dynamic polarization encoding of deterministically generated single photons

Joscha Hanel, Zenghui Jiang, Jipeng Wang +10

The ability to inscribe information on single photons at high speeds is a crucial requirement for quantum applications such as quantum communication and measurement-based photonic…

On the Differential Topology of Expressivity of Parameterized Quantum Circuits

Johanna Barzen, Frank Leymann

Parameterized quantum circuits play a key role in quantum computing. Measuring the suitability of such a circuit for solving a class of problems is needed. One such promising measu…

Asymmetric two-photon response of an incoherently driven quantum emitter

Lennart Jehle, Lena M. Hansen, Patrik I. Sund +7

Quantum emitters promise to emit exactly one photon with high probability when pumped by a laser pulse. However, even in ideal systems, re-excitation during a laser pulse causes th…

Suppressing crosstalk for Rydberg quantum gates

Gina Warttmann, Florian Meinert, Hans Peter Büchler +1

We present a method to suppress crosstalk from implementing controlled-Z gates via local addressing in neutral atom quantum computers. In these systems, a fraction of the laser lig…

Quantum-network nodes with real-time noise mitigation using spectator qubits

S. J. H. Loenen, Y. Wang, N. Demetriou +2

Quantum networks might enable quantum communication and distributed quantum computation. Solid-state defects are promising platforms for such networks, because they provide an opti…

Sensing single molecule magnets with nitrogen vacancy centers

Ariel Smooha, Jitender Kumar, Dan Yudilevich +12

Single-molecule magnets (SMMs) are molecules that can function as nanoscale magnets with potential use as magnetic memory bits. While SMMs can retain magnetization at low temperatu…

Measurement-free quantum error correction optimized for biased noise

Katharina Brechtelsbauer, Friederike Butt, David F. Locher +4

In this paper, we derive optimized measurement-free protocols for quantum error correction and the implementation of a universal gate set optimized for an error model that is noise…

Simultaneous sweet-spot locking of gradiometric fluxonium qubits

Denis Bénâtre, Mathieu Féchant, Nicolas Zapata +4

Efforts to scale up superconducting processors that employ flux-qubits face numerous challenges, among which is the crosstalk created by neighboring flux lines, which are necessary…

quant-ph2025★ 7 cited

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…

quant-ph2025★ 4 cited

Initialization of Neutral and Charged Exciton Spin States in a Telecom-Emitting Quantum Dot

Giora Peniakov, Johannes Michl, Mohamed Helal +6

Photonic cluster states are highly entangled states that allow for photonic quantum computing and memory-less quantum repeaters. Their generation has been recently demonstrated usi…

quant-ph2025★ 33 cited

Roadmap on Quantum Thermodynamics

Steve Campbell, Irene D'Amico, Mario A. Ciampini +66

The last two decades has seen quantum thermodynamics become a well established field of research in its own right. In that time, it has demonstrated a remarkably broad applicabilit…

quant-ph2025★ 5 cited

Quantum vs. classical: A comprehensive benchmark study for predicting time series with variational quantum machine learning

Tobias Fellner, David Kreplin, Samuel Tovey +1

Variational quantum machine learning algorithms have been proposed as promising tools for time series prediction, with the potential to handle complex sequential data more effectiv…

Light Storage in Light Cages: A Scalable Platform for Multiplexed Quantum Memories

Esteban Gómez-López, Dominik Ritter, Jisoo Kim +3

Quantum memories are essential for photonic quantum technologies, enabling long-distance quantum communication and serving as delay units in quantum computing. Hot atomic vapors us…

quant-ph2025★ 3 cited

Optimized noise-resilient surface code teleportation interfaces

Mohamed A. Shalby, Renyu Wang, Denis Sedov +1

Connecting two surface-code patches may require significantly higher noise at the interface. We show, via circuit-level simulations under a depolarizing noise model with idle error…