A5048611499- Physics of Superconductivity and Magnetism
- Quantum many-body systems
- Cold Atom Physics and Bose-Einstein Condensates
- Algorithms and Data Compression
- Quantum Chromodynamics and Particle Interactions
- Black Holes and Theoretical Physics
- Advanced Condensed Matter Physics
- Medical Imaging Techniques and Applications
- Quantum and electron transport phenomena
- Computational Physics and Python Applications
- Theoretical and Computational Physics
- Advanced Biosensing Techniques and Applications
- Iron-based superconductors research
- Quantum, superfluid, helium dynamics
- Quantum Computing Algorithms and Architecture
- Medical Imaging and Pathology Studies
- Magnetic and transport properties of perovskites and related materials
- Advanced Thermodynamics and Statistical Mechanics
- Quantum Information and Cryptography
- Advanced MRI Techniques and Applications
- Superconducting Materials and Applications
- Machine Learning in Materials Science
- Magnetic properties of thin films
- Electronic and Structural Properties of Oxides
- Atomic and Subatomic Physics Research
Munich Center for Quantum Science and Technology
2019-2025
University of Regensburg
2023-2025
Technical University of Munich
2017-2024
Institute for Advanced Study
2017-2024
Center for Astrophysics Harvard & Smithsonian
2021-2024
Harvard University
2017-2024
Harvard University Press
2021-2024
Institute on Taxation and Economic Policy
2022
University of Kaiserslautern
2018
Schott (Germany)
2017
Abstract Conventional superconductivity emerges from pairing of charge carriers—electrons or holes—mediated by phonons 1 . In many unconventional superconductors, the mechanism is conjectured to be mediated magnetic correlations 2 , as captured models mobile charges in doped antiferromagnets 3 However, a precise understanding underlying real materials still lacking and has been driving experimental theoretical research for past 40 years. Early studies predicted magnetic-mediated dopants...
Since the discovery of superconductivity in cuprate materials, minimal ingredients for high-${T}_{c}$ have been an outstanding puzzle. Motivated by recently discovered nickelate bilayer superconductor ${\mathrm{La}}_{3}{\mathrm{Ni}}_{2}{\mathrm{O}}_{7}$ under pressure, we study a model, which, as ${\mathrm{La}}_{3}{\mathrm{Ni}}_{2}{\mathrm{O}}_{7}$, interlayer and intralayer magnetic interactions but no hopping are present: A mixed-dimensional (mixD) $t\text{\ensuremath{-}}J$ model. In...
Abstract The relation between d -wave superconductivity and stripes is fundamental to the understanding of ordered phases in high-temperature cuprate superconductors 1–6 . These can be strongly influenced by anisotropic couplings, leading higher critical temperatures, as emphasized recent discovery nickelates 7–10 Quantum simulators with ultracold atoms provide a versatile platform engineer such couplings observe emergent structures real space single-particle resolution. Here we show, our...
Owing to their great expressivity and versatility, neural networks have gained attention for simulating large two-dimensional quantum many-body systems. However, comes with the cost of a challenging optimization due in general rugged complicated loss landscape. Here, we present hybrid scheme states (NQS) that involves data-driven pretraining numerical or experimental data second, Hamiltonian-driven stage. By using both projective measurements from computational basis as well expectation...
Abstract Resonant interactions associated with the emergence of a bound state constitute one cornerstones modern many-body physics. Here we present Feshbach perspective on origin strong pairing in Fermi-Hubbard type models. We perform theoretical analysis between spin-polaron charge carriers doped Mott insulators, modeled by near-resonant two-channel scattering problem, and report evidence for Feshbach-type $${d}_{{x}^{2}-{y}^{2}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML">...
Out-of-time ordered (OTO) correlation functions describe scrambling of information in correlated quantum matter. They are particular interest incoherent systems lacking well defined quasi-particles. Thus far, it is largely elusive how OTO correlators spread with diffusive transport governed by a few globally conserved quantities. Here, we study the dynamical response such system using high-performance matrix-product-operator techniques. Specifically, consider non-integrable, one-dimensional...
When a mobile hole is moving in an anti-ferromagnet it distorts the surrounding Neel order and forms magnetic polaron. Such interplay between motion anti-ferromagnetism believed to be at heart of high-Tc superconductivity cuprates. We study single described by t-Jz model with Ising interactions spins 2D. This situation can experimentally realized quantum gas microscopes. hopping much larger than couplings spins, we find strong evidence that polarons understood as bound states two partons,...
The competition between antiferromagnetism and hole motion in two-dimensional Mott insulators lies at the heart of a doping-dependent transition from an anomalous metal to conventional Fermi liquid. Condensed matter experiments suggest charge carriers change their nature within this crossover, but complete understanding remains elusive. We observe such crossover Fermi-Hubbard systems on cold-atom quantum simulator reveal transformation multi-point correlations spins holes upon increasing...
Looking for patterns in an optical lattice One of the simplest models interacting fermions on a two-dimensional (2D) lattice—the Hubbard model—becomes too tricky to simulate classical computers as density empty sites (holes) increases. Chiu et al. used quantum microscope take snapshots thousands realizations 2D model filled with fermionic lithium atoms at varying hole densities (see Perspective by Schauss). The authors pattern recognition algorithms analyze images, which each site was...
Interacting many-body systems combining confined and extended dimensions, such as ladders few layer are characterized by enhanced quantum fluctuations, which often result in interesting collective properties. Recently two-dimensional bilayer systems, twisted graphene or ultracold atoms, have sparked a lot of interest because they can host rich phase diagrams, including unconventional superconductivity. Here we present theoretical proposal for realizing high temperature pairing fermions class...
The interplay of interactions and strong disorder can lead to an exotic quantum many-body localized (MBL) phase matter. Beyond the absence transport, MBL has distinctive signatures, such as slow dephasing logarithmic entanglement growth; they commonly result in subtle modifications dynamics, rendering their measurement challenging. Here, we experimentally characterize these properties a system coupled superconducting qubits. By implementing sensitive techniques, map out structure local...
Gauge fields coupled to dynamical matter are ubiquitous in many disciplines of physics, ranging from particle condensed but their implementation large-scale quantum simulators remains challenging. Here we propose a realistic scheme for Rydberg atom array experiments which $\mathbb{Z}_2$ gauge structure with charges emerges on experimentally relevant timescales only local two-body interactions and one-body terms two spatial dimensions. The enables the experimental study variety models,...
Abstract Ever since the discovery of high-temperature superconductivity in cuprates, gaining microscopic insights into nature pairing strongly correlated systems has remained one greatest challenges modern condensed matter physics. Following recent experiments reporting bilayer nickelate La 3 Ni 2 O 7 (LNO) with remarkably high critical temperatures T c = 80 K, it been argued that low-energy physics LNO can be described by correlated, mixed-dimensional t – J model. Here we investigate this...
Understanding unconventional superconductivity involves unraveling the pairing mechanism of charge carriers in doped antiferromagnets, where Cooper pairs form despite repulsive interactions. This paper examines a model relevant to bilayer nickelate superconductors, revealing transition from tightly bound spatially extended as repulsion increases. At strong repulsion, microscopic is identified that leads robust with peak binding energies at around 30% doping, which can be tested using quantum...
The combination of optical tweezer arrays with strong interactions---via dipole exchange molecules and Van der Waals interactions Rydberg atoms---has opened the door for exploration a wide variety quantum spin models. A next significant step will be such settings mobile dopants. This enable one to simulate physics believed underlie many strongly correlated materials. Here, we propose an experimental scheme realize bosonic $t--J$ models via encoding local Hilbert space in set three internal...
Abstract Numerically simulating large, spinful, fermionic systems is of great interest in condensed matter physics. However, the exponential growth Hilbert space dimension with system size renders exact quantum state parameterizations impractical. Owing to their representative power, neural networks often allow overcome this scaling. Here, we investigate ability states (NQS) represent bosonic and t − J model – high interaction limit Hubbard on various 1D 2D lattices. Using autoregressive,...
Quantum gas microscopes are a promising tool to study interacting quantum many-body systems and bridge the gap between theoretical models real materials. One of most powerful experimental methods in solids is angle-resolved photoemission spectroscopy (ARPES), which measures single-particle spectral function. The authors propose measurement scheme experimentally access momentum- energy-resolved function microscope. As an example for possible applications, spectrum single hole excitation...
Angle-resolved photoemission spectroscopy (ARPES) has revealed peculiar properties of mobile dopants in correlated anti-ferromagnets (AFMs). But describing them theoretically, even simplified toy models, remains a challenge. Here we study ARPES spectra single hole the $t-J$ model. Recent progress microscopic description allows us to use geometric decoupling spin and charge fluctuations at strong couplings, from which conjecture one-to-one relation one-dopant spectral function spectrum...
Disorder-free localization is a recently discovered phenomenon of nonergodicity that can emerge in quantum many-body systems hosting gauge symmetries when the initial state prepared superposition superselection sectors. Thermalization then prevented up to all accessible evolution times despite model being nonintegrable and translation invariant. In recent work [Halimeh et al., arXiv:2111.02427 (2021)], it has been shown terms linear gauge-symmetry generator stabilize disorder-free U(1)...
Quantum many-body scarring is a paradigm of weak ergodicity breaking arising due to the presence special nonthermal eigenstates that possess low entanglement entropy, are equally spaced in energy, and concentrate certain parts Hilbert space. Though scars have been shown be intimately connected gauge theories, their stability such experimentally relevant models still an open question, it generally considered they exist only under fine-tuned conditions. In this work, we show through...
In strongly correlated quantum materials, the behavior of charge carriers is dominated by strong electron-electron interactions. These can lead to insulating states with spin order, and upon doping competing ordered including unconventional superconductivity. The underlying pairing mechanism remains poorly understood however, even in simplified theoretical models. Recent advances simulation allow study paradigmatic settings, e.g. t-J <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"...
Programmable quantum simulators based on Rydberg atom arrays are a fast-emerging platform, bringing together long coherence times, high-fidelity operations, and large numbers of interacting qubits deterministically arranged in flexible geometries. Today's array devices demonstrating their utility as for studying phases phase transitions matter. In this paper, we show that unprocessed imperfect experimental projective measurement data can be used to enhance silico simulations matter, by...