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The 1-form symmetry, manifesting as loop-like symmetries, has gained prominence in the study of quantum phases, deepening our understanding of symmetry. However, the role of 1-form symmetries in Projected Entangled-Pair States (PEPS), two-dimensional tensor network states, remains largely underexplored. We present a novel framework for understanding 1-form symmetries within tensor networks, specifically focusing on the derivation of algebraic relations for symmetry matrices on the PEPS virtual legs. Our results reveal that 1-form symmetries impose stringent constraints on tensor network representations, leading to distinct anomalous braiding phases carried by symmetry matrices. We demonstrate how these symmetries influence the ground state and tangent space in PEPS, providing new insights into their physical implications for enhancing ground state optimization efficiency and characterizing the 1-form symmetry structure in excited states.
We study the random transverse field Ising model on a finite Cayley tree. This enables us to probe key questions arising in other important disordered quantum systems, in particular the Anderson transition and the problem of dirty bosons on the Cayley tree, or the emergence of non-ergodic properties in such systems. We numerically investigate this problem building on the cavity mean-field method complemented by state-of-the art finite-size scaling analysis. Our numerics agree very well with analytical results based on an analogy with the traveling wave problem of a branching random walk in the presence of an absorbing wall. Critical properties and finite-size corrections for the zero-temperature paramagnetic-ferromagnetic transition are studied both for constant and algebraically vanishing boundary conditions. In the later case, we reveal a regime which is reminiscent of the non-ergodic delocalized phase observed in other systems, thus shedding some light on critical issues in the context of disordered quantum systems, such as Anderson transitions, the many-body localization or disordered bosons in infinite dimensions.
A relativistic action for scalar condensate-fermion mixture is considered where both the scalar boson and the fermion fields are coupled to a $U(1)$ gauge field. The dynamics of the gauge field is governed by a linear combination of the Maxwell term and the Lorentz invariant $\mathbf{E\cdot B}$ term with a constant coefficient $\theta$. We obtain an effective action describing an emergent fermion-fermion interaction and fermion-vortex tube interaction by using the particle-string duality, and find that the $\theta$ term can significantly affect the interaction of fermions and vortices. We also perform a dimensional reduction to show a $\theta$ dependent flux attachment to the itinerant fermions.
Landau's Fermi-liquid (FL) theory has been successful at the phenomenological description of the normal phase of many different Fermi systems. Using a dilute atomic Fermi fluid with tunable interactions, we investigate the microscopic basis of Landau's theory with a system describable from first principles. We study transport properties of an interacting Fermi gas by measuring its density response to a periodic external perturbation. In an ideal Fermi gas, we measure for the first time the celebrated Lindhard function. As the system is brought from the collisionless to the hydrodynamic regime, we observe the emergence of sound, and find that the experimental observations are quantitatively understood with a first-principle transport equation for the FL. When the system is more strongly interacting, we find deviations from such predictions. Finally, we observe the shape of the quasiparticle excitations directly from momentum-space tomography and see how it evolves from the collisionless to the collisional regime. Our study establishes this system as a clean platform for studying Landau's theory of the FL and paves the way for extending the theory to more exotic conditions, such as nonlinear dynamics and FLs with strong correlations in versatile settings.
In this work, building on state-of-the-art quantum Monte Carlo simulations, we perform systematic finite-size scaling of both entanglement and participation entropies for long-range Heisenberg chain with unfrustrated power-law decaying interactions. We find distinctive scaling behaviors for both quantum entropies in the various regimes explored by tuning the decay exponent $\alpha$, thus capturing non-trivial features through logarithmic terms, beyond the case of linear Nambu-Goldstone modes. Our systematic analysis reveals that the quantum entanglement information, hidden in the scaling of the two studied entropies, can be obtained to the same level of order parameters and other usual finite-size observables of quantum many-body lattice models. The analysis and results obtained here can readily apply to more quantum criticalities in 1D and 2D systems.
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Boson scalar
Low-dimensional systems
Entanglement
0270Ss
Solids
Strong interaction
Bose glass
Supraconductivité
Numerical methods
Deconfinement
Spin liquids
Entanglement quantum
Critical phenomena
Dimeres
7130+h
Liquid
Théorie de la matière condensée
Boson
Systèmes fortement corrélés
Quantum physics
Apprentissage automatique
Advanced numerical methods
Chaînes des jonctions
7127+a
Collective modes
Monte-Carlo quantique
Frustration
Quantum magnetism
Superconductivity cond-matsupr-con
Strongly Correlated Electrons cond-matstr-el
Quantum dimer models t-J model
Magnetic quantum oscillations
Excited state
Variational quantum Monte Carlo
Atom
Strongly Correlated Electrons
Antiferromagnetic conductors
7510Jm
Antiferromagnétisme
Spin
Condensed matter theory
T-J model
7510Kt
FOS Physical sciences
Collinear
Basse dimension
Valence bond crystals
Dimension
Ground state
Axion
Network
Strongly correlated systems
Quasiparticle
Méthodes numériques
Thermodynamical
Correlation
6470Tg
Anyons
Low dimension
Spin chain
Kagome lattice
Magnetism
Aimants quantiques
Gas
Classical spin liquid
Magnétisme quantique
Electronic structure and strongly correlated systems
Arrays of Josephson junctions
Physique quantique
Disorder
Chaines de spin
Quantum dimer models t-J model superconductivity magnetism
Atomic Physics physicsatom-ph
Superconductivity
Réseaux de tenseurs
Color
Gauge field theory
Polaron
Dirac spin liquid
Anti-ferromagnetism
Plateaux d'aimantation
High-Tc
Électrons fortement corrélés
Variational Monte Carlo
Many-body problem
Quantum information
Condensed matter physics
Condensed Matter
Antiferromagnetism
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7540Mg
Physique de la matière condensée
Heisenberg model
Quantum Gases cond-matquant-gas
Tensor networks
Chaines de spin1/2
Bosons de coeur dur
Champ magnétique
Benchmark