Symmetric approximant formalism for statistical topological matter

Kavli Affiliate: Anton Akhmerov | Summary:The standard approach to characterizing topological matter, computing topological invariants, fails when the symmetry protecting the topological phase is preserved only on average in a disordered system. Because topological invariants rely on enforcing the symmetry exactly, they can overcount phases by incorrectly identifying certain non-robust features as robust. Moreover, in […]


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Automated electrostatic characterization of quantum dot devices in single- and bilayer heterostructures

Kavli Affiliate: Menno Veldhorst | Summary:As quantum dot (QD)-based spin qubits advance toward larger, more complex device architectures, rapid, automated device characterization and data analysis tools become critical. The orientation and spacing of transition lines in a charge stability diagram (CSD) contain a fingerprint of a QD device’s capacitive environment, making these measurements useful tools […]


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Towards autonomous time-calibration of large quantum-dot devices: Detection, real-time feedback, and noise spectroscopy

Kavli Affiliate: Menno Veldhorst | Summary:The performance and scalability of semiconductor quantum-dot (QD) qubits are limited by electrostatic drift and charge noise that shift operating points and destabilize qubit parameters. As systems expand to large one- and two-dimensional arrays, manual recalibration becomes impractical, creating a need for autonomous stabilization frameworks. Here, we introduce a method […]


Continue.. Towards autonomous time-calibration of large quantum-dot devices: Detection, real-time feedback, and noise spectroscopy

Novel qubits in hybrid semiconductor-superconductor nanostructures

Kavli Affiliate: Srijit Goswami | Summary:Hybrid semiconductor-superconductor qubits have recently emerged as a promising alternative to traditional platforms, combining material advantages with device-level tunability. A defining feature is their gate-tunable Josephson coupling, enabling superconducting qubit architectures with full electric-field control and offering a path toward scalable, low-crosstalk quantum processors. This approach seeks to merge benefits […]


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Highly Tunable Two-Qubit Interactions in Si/SiGe Quantum Dots by Interchanging the Roles of Qubit-Defining Gates

Kavli Affiliate: Giordano Scappucci | Summary:Silicon quantum dot spin qubits have become a promising platform for scalable quantum computing because of their small size and compatibility with industrial semiconductor manufacturing processes. Although Si/SiGe heterostructures are commonly used to host spin qubits due to their high mobility and low percolation density, the SiGe spacer creates a […]


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Driving the field-free Josephson diode effect using Kagome Mott insulator barriers

Kavli Affiliate: Mazhar Ali | Summary: Josephson junctions (JJs), devices consisting of two superconductors separated by a barrier, are of great technological importance, being a cornerstone of quantum information processing. Classical understanding of superconductor-insulator-superconductor JJs is that conventional insulator’s properties, other than magnetism, do not significantly influence the junction’s behavior. However, recent work on quantum […]


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Probing ground-state degeneracies of a strongly interacting Fermi-Hubbard model with superconducting correlations

Kavli Affiliate: Michael Wimmer | Summary:The Fermi-Hubbard model and its rich phase diagram naturally emerges as a description for a wide range of electronic systems. Recent advances in semiconductor-superconductor hybrid quantum dot arrays have allowed to realize degenerate quantum systems in a controllable way, e.g., allowing to observe robust zero-bias peaks in Kitaev chains, indicative […]


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Nuclear magnetic resonance on a single atom with a local probe

Kavli Affiliate: Sander Otte | Summary:The nuclear spin is a prime candidate for quantum information applications due to its weak coupling to the environment and inherently long coherence times. However, this weak coupling also challenges the addressability of the nuclear spin. Here we demonstrate nuclear magnetic resonance (NMR) on a single on-surface atom using a […]


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Extreme statistics as a probe of the superfluid to Bose-glass Berezinskii-Kosterlitz-Thouless transition

Kavli Affiliate: Natalia Chepiga | Summary:Recent studies of delocalization-localization transitions in disordered quantum chains have highlighted the role of rare, chain-breaking events that favor localization, in particular for high-energy eigenstates related to many-body localization. In this context, we revisit the random-field XXZ spin-1/2 chain at zero temperature with ferromagnetic interactions, equivalent to interacting fermions or […]


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A Three-Dimensional Array of Quantum Dots

Kavli Affiliate: Menno Veldhorst | Summary:Quantum dots can confine single electrons or holes to define spin qubits that can be operated with high fidelity. Experimental work has progressed from linear to two-dimensional arrays of quantum dots, enabling qubit interactions that are essential for quantum simulation and computation. Here, we explore architectures beyond planar geometries by […]


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