Entanglement based observables for quantum impurities

Abstract

Quantum impurities exhibit fascinating many-body phenomena when the small interacting impurity changes the physics of a large noninteracting environment. The characterisation of such strongly correlated non-perturbative effects is particularly challenging due to the infinite size of the environment, and the inability of local correlators to capture the build-up of long-ranged entanglement in the system. Here, we harness an entanglement-based observable - the purity of the impurity - as a witness for the formation of strong correlations. We showcase the utility of our scheme by exactly solving the open Kondo box model in the small box limit, and thus describe all-electronic dot-cavity devices. Specifically, we conclusively characterise the metal-to-insulator phase transition in the system and identify how the (conducting) dot-lead Kondo singlet is quenched by an (insulating) intra-impurity singlet formation. Furthermore, we propose an experimentally feasible tomography protocol for the measurement of the purity, which motivates the observation of impurity physics through their entanglement build-up.

arXiv comment6 pages, 4 figures, comments are welcome

References in corpus (34)

• Quantum Computing in the NISQ era and beyond
• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• The density-matrix renormalization group in the age of matrix product states
• Quantum Simulation
• Continuous-time Monte Carlo methods for quantum impurity models
• The numerical renormalization group method for quantum impurity systems
• Controlled Collisions for Multiparticle Entanglement of Optically Trapped Atoms
• Time-evolution methods for matrix-product states
• Perspectives of quantum annealing: Methods and implementations
• Silicon quantum processor unit cell operation above one Kelvin
• The Kondo Box: A Magnetic Impurity in an Ultrasmall Metallic Grain
• Variational matrix product state approach to quantum impurity models
• Negativity as the Entanglement Measure to Probe the Kondo Regime in the Spin-Chain Kondo Model
• Entanglement probe of two-impurity Kondo physics in a spin chain
• Zero-field Kondo splitting and quantum-critical transition in double quantum dots
• Transport properties and Kondo correlations in nanostructures: the time-dependent DMRG method applied to quantum dots coupled to Wilson chains
• How to measure the entropy of a mesoscopic system via thermoelectric transport
• Realizing a Deterministic Source of Multipartite-Entangled Photonic Qubits
• Thermal vs. Entanglement Entropy: A Measurement Protocol for Fermionic Atoms with a Quantum Gas Microscope
• Matrix product state comparison of the numerical renormalization group and the variational formulation of the density matrix renormalization group
• Symmetric inseparability and number entanglement in charge conserving mixed states
• Macroscopic Quantum Entanglement of a Kondo Cloud at Finite Temperature
• Quantum simulation of Anderson and Kondo lattices with superconducting qubits
• Renormalized Lindblad Driving: A Numerically-Exact Nonequilibrium Quantum Impurity Solver
• Transport Spectroscopy of a Spin-Coherent Dot-Cavity System
• Spin-polarized conductance in double quantum dots: Interplay of Kondo, Zeeman and interference effects
• Impurity entanglement entropy in Kondo systems from conformal field theory
• Bell-state tomography in a silicon many-electron artificial molecule
• Universal Thermal Entanglement of Multichannel Kondo Effects
• Long-range spin-coherence in a strongly-coupled all electronic dot-cavity system
• Cavity-mediated coherent coupling between distant quantum dots
• Conductance and Kondo Interference beyond Proportional Coupling
• Complete state tomography of a quantum dot confined spin qubit
• Orbital magnetic properties of quantum dots: the role of electron-electron interactions

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• Next-generation EDIpack: A Lanczos-based package for quantum impurity models featuring general broken-symmetry phases, flexible bath topologies and multi-platform interoperability
• Coherent exchange-coupled nonlocal Kondo impurities
• Quantum entanglement in a pure state of strongly correlated quantum impurity systems
• Ballistic Entanglement Cloud after a Boundary Quench
• Unraveling screening mechanisms in Kondo impurities using an NRG-MPS-based method