Research Groups
Bernien Lab - Quantum Science Atom-by-Atom

The BernienLab studies quantum science by assembling large quantum systems using individual atoms trapped in optical tweezers. This platform is ideally suited to both explore fundamental questions,... Read more …
Ferlaino Lab - Dipolar Quantum Gases

The research team led by Francesca Ferlaino focuses on the study of dipolar quantum phenomena, using strongly magnetic atomic species. In 2012, the group has created the first Bose-Einstein... Read more …
Grimm Lab - Ultracold Atoms and Quantum Gases

The research group led by R. GRIMM investigates ultracold particle systems consisting of optically trapped quantum gases at temperatures close to absolute zero. Because of their superb experimental... Read more …
Hammerer Group - Quantum Optics and Quantum Metrology

The Hammerer group conducts research in theoretical quantum optics, with a particular focus on quantum metrology and precision measurement. We study physical systems that can be described and... Read more …
Kirchmair Lab - Superconducting quantum circuits

Gerhard Kirchmair’s research group works on superconducting circuits and their application for quantum computation and simulation. Superconducting Josephson junctions are used to realize the quantum... Read more …
Pichler Group - Quantum Science Theory

The research group led by Hannes Pichler studies quantum optical systems, quantum many-body physics and quantum information. The group aims at laying the theoretical foundations for next generation... Read more …
Emeritus Research Groups
Blatt Lab - Quantum Optics and Spectroscopy

The research group led by Rainer Blatt investigates quantum processes in a system of few ions held in ion traps. The experiments aim at achieving complete control over all quantum degrees of freedom in... Read more …
Zoller Group - Quantum Optics

Wittgenstein awardee Peter Zoller studies topics in the fields of theoretical quantum optics and atomic physics as well as quantum information and condensed matter theory. His main focus is on... Read more …
Most Recent Preprints
Neural quantum states for emitter dynamics in waveguide QED
arXiv:2508.08964
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Quantum emitters coupled to one-dimensional waveguides constitute a paradigmatic quantum-optical platform for exploring collective phenomena in open quantum many-body systems. For appropriately spaced emitters, they realize the Dicke model, whose characteristic permutation symmetry allows for efficient exact solutions featuring superradiance. When the emitters are arbitrarily spaced, however, this symmetry is lost and general analytical solutions are no longer available. In this work, we introduce a novel numerical method to study the dynamics of such systems by extending the time-dependent neural quantum state (t-NQS) framework to open quantum systems. We benchmark our approach across a range of waveguide QED settings and compare its performance with tensor-network calculations. Our results demonstrate that the t-NQS approach is competitive with other numerical methods and highlight the potential of t-NQSs for studying open quantum many-body systems out of equilibrium.
Learning mixed quantum states in large-scale experiments
arXiv:2507.12550
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More Preprints
We present and test a protocol to learn the matrix-product operator (MPO) representation of an experimentally prepared quantum state. The protocol takes as an input classical shadows corresponding to local randomized measurements, and outputs the tensors of a MPO which maximizes a suitably-defined fidelity with the experimental state. The tensor optimization is carried out sequentially, similarly to the well-known density matrix renormalization group algorithm. Our approach is provably efficient under certain technical conditions which are expected to be met in short-range correlated states and in typical noisy experimental settings. Under the same conditions, we also provide an efficient scheme to estimate fidelities between the learned and the experimental states. We experimentally demonstrate our protocol by learning entangled quantum states of up to qubits in a superconducting quantum processor. Our method upgrades classical shadows to large-scale quantum computation and simulation experiments.
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