Article
Computer Science, Interdisciplinary Applications
Xu He, Nicole Helbig, Matthieu J. Verstraete, Eric Bousquet
Summary: TB2J is a Python package for the automatic computation of magnetic interactions in magnetic crystals based on density functional calculations. It requires only one first-principles electronic structure calculation in the non-relativistic case, and can be directly used for adiabatic magnon band structure and spin dynamics calculations. Its main advantage lies in its minimal user input requirement and easy integration into high-throughput workflows.
COMPUTER PHYSICS COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Conor Stevenson, Bernd Braunecker
Summary: It is shown that in a quantum wire with a local asymmetric scattering potential, the principal channels for charge and heat transport decouple and renormalize differently under electron interactions, with heat transport generally being more relevant. The polarization of the rectification results from quantum interference and can be tuned through external gating. Additionally, for spin-polarized or helical electrons with strong interactions, a regime can be achieved where heat transport is strongly rectified while charge rectification is weak.
Article
Physics, Multidisciplinary
Xinghai Zhang, Matthew S. Foster
Summary: This study explores quantum quenches of helical liquids with spin-flip inelastic scattering, revealing two types of strongly nonlinear wave dynamics caused by localized hot spots formed due to scattering. The experimental results suggest potential for verification through the detection of frequency doubling from emitted terahertz radiation.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Moallison F. Cavalcante, Rodrigo G. Pereira, Maria C. O. Aguiar
Summary: We investigate the dynamics of the Kondo effect in a system of two metallic Hubbard chains coupled to a magnetic impurity after a quantum quench. For noninteracting electrons, the charge current across the impurity is determined by a scaling function involving the Kondo time. In the case of interacting electrons, we observe a decrease in the Kondo time with increasing repulsive interaction strength, and the time dependence of the current exhibits characteristics of the Kondo effect in a Luttinger liquid. Our findings emphasize the significance of nonequilibrium dynamics in studying quantum impurities in interacting systems.
Article
Materials Science, Multidisciplinary
Imke Schneider, Ipsita Mandal, Polina Matveeva, Dominik Strassel, Sebastian Eggert
Summary: The asymptotic dynamical correlation functions in one-dimensional spin chains follow power laws, with corresponding exponents characterizing different bulk and boundary critical behavior. Results for the logarithmic contribution to boundary correlations in an isotropic Heisenberg chain are presented, and the logarithm exponent of λ = 1 is derived using renormalization group technique. Analytical results are confirmed by comparison with numerical quantum Monte Carlo data.
Article
Quantum Science & Technology
Yichen Hu, Biao Lian
Summary: We investigate the homogeneous chiral edge theory of the filling v = 4/3 fractional quantum Hall state, and identify two solvable cases. We find that the energy spectrum shows Poisson level spacing statistics and can transition to Wigner-Dyson with the inclusion of a global symmetry preserving irrelevant nonlinear kinetic term.
Article
Materials Science, Multidisciplinary
Tony Jin, Paola Ruggiero, Thierry Giamarchi
Summary: We derive the bosonization of the interacting fermionic Su-Schrieffer-Heeger (SSH) model with open boundaries and use it to quantitatively describe the edge modes of the system. Our results show excellent agreement with numerical simulations, particularly in terms of the localization of the zero-energy edge mode near the boundaries. Interestingly, we find that the effects of repulsive or attractive interactions on the edge mode localization depend on the staggering parameter. We provide quantitative predictions of these effects on the localization length of the edge mode and suggest that bosonization can be generalized to other models.
Article
Materials Science, Multidisciplinary
Assaf Voliovich, Mark S. Rudner, Yuval Oreg, Erez Berg
Summary: In this study, we investigate competing insulating phases in nearly metallic zigzag carbon nanotubes. We find that an applied magnetic flux does not close and reopen the single-particle gap near a specific valley. By using a bosonic low-energy effective theory, we construct a phase diagram that shows several competing insulating phases that can form near the closing point of the single-particle gap. These phases are characterized by spin-resolved charge polarization densities, and can take different values due to mirror symmetry breaking. In the mirror symmetry breaking phase, adiabatic changes of the orbital magnetic flux drive charge and spin currents along the nanotube.
Article
Physics, Multidisciplinary
Per Moosavi
Summary: This article studies the Tomonaga-Luttinger liquid theory that describes inhomogeneous quantum Hall edges with analytical methods, obtaining exact solutions for the dynamics of the system. The results show a remarkably universal dependence on details during the long-time evolution following quantum quenches.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Multidisciplinary
Clement De Daniloff, Marin Tharrault, Cedric Enesa, Christophe Salomon, Frederic Chevy, Thomas Reimann, Julian Struck
Summary: We studied ensembles of fermionic cold-atom quantum wires with tunable transverse mode population and single-wire resolution. By controlling the temperature and atom number, we were able to observe the 1D-3D crossover and investigate the equilibrium and transport properties of strongly interacting 1D Fermi gases.
PHYSICAL REVIEW LETTERS
(2021)
Article
Mathematics, Applied
Wen-ming He, Hailong Guo
Summary: This study investigates the maximum norm error estimations for virtual element methods, establishing higher local regularity and optimal convergence results through analysis of Green's functions and high-order local error estimations for the virtual element solutions. The theoretical discoveries are validated with a numerical example on general polygonal meshes.
SIAM JOURNAL ON NUMERICAL ANALYSIS
(2022)
Article
Physics, Multidisciplinary
He-Yu Lin, Rong-Qiang He, Zhong-Yi Lu
Summary: In this paper, a new method combining the Green's function Monte Carlo (GFMC) method with the restricted Boltzmann machine (RBM) is proposed to study the ground state of quantum many-body systems. The results show that the GFMC method can significantly reduce the relative error of the ground-state energy based on the RBM variational results, which provides a potential approach for combining the GFMC method with other neural networks to deal with models with sign problem.
Article
Materials Science, Multidisciplinary
Balazs Dora, Miklos Antal Werner, Catalin Pascu Moca
Summary: The quantum quench dynamics of the interacting Hatano-Nelson model with open boundary conditions is investigated using Abelian bosonization and numerical methods. The evolution of particle density and current profile in real space over time is followed by turning on or off the imaginary vector potential in the presence of weak interactions. The results show spatiotemporal Friedel oscillations with light cones propagating ballistically from the open ends, accompanied by local currents of equal magnitude for both switching protocols. The bosonization method accurately describes the density and current patterns with a single overall fitting parameter. The continuity equation is satisfied by the long-wavelength part of the density and current, despite the nonunitary time evolution when the Hatano-Nelson term is switched on.
Article
Optics
Omar Abel Rodriguez-Lopez, M. A. Solis, J. Boronat
Summary: We study the structural superfluid-Mott-insulator quantum phase transition of an interacting one-dimensional Bose gas within multirod lattices, and use the ab initio diffusion Monte Carlo method to calculate relevant parameters. We find that varying the width of barriers from zero to the length of the potential period can induce the SF-MI phase transition.
Review
Crystallography
Niccolo Traverso Ziani, Fabio Cavaliere, Karina Guerrero Becerra, Maura Sassetti
Summary: This review discusses the simplest structural transition of Wigner crystallization in electronic systems and three recent experiments on one-dimensional Wigner molecules. The Luttinger liquid theory and basic properties of carbon nanotubes are briefly addressed, followed by discussions on the relevant properties of Wigner molecules and descriptions of the experiments. Key physical points include the suppression of energy scales related to the spin and isospin sectors, and the unique electron density structure in the Wigner molecule regime.
Article
Physics, Multidisciplinary
Shengtao Jiang, Judit Romhanyi, Steven R. White, M. E. Zhitomirsky, A. L. Chernyshev
Summary: We present strong evidence for the spin-nematic state in a paradigmatic ferro-antiferromagnetic J1-J2 model using analytical and density-matrix renormalization group methods. In the absence of an external magnetic field, spin-flip pairs attract each other and result in a first-order transition without the formation of a nematic state. However, with larger J2, the repulsion between spin-flip pairs stabilizes the nematic phase in a narrow region close to the pair-condensation field. For weak pair attraction, a devil’s staircase of multipair condensates is proposed. The size of the nematic phase is significantly smaller than expected due to the suppression of the spin-flip gap by many-body effects. The proposed phase diagram is expected to be universally valid.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Multidisciplinary
Hernan B. Xavier, Claudio Chamon, Rodrigo G. Pereira
Summary: We construct a family of topological chiral spin liquids in 2D using a network of chiral junctions. The phase exhibits SU(2)k anyons derived from the underlying SU(2)k WZW models of the constituent spin chains. The network displays quantized spin and thermal Hall conductances.
Editorial Material
Physics, Applied
Steven R. White
NATURE REVIEWS PHYSICS
(2023)
Article
Physics, Multidisciplinary
Weslei B. Fontana, Rodrigo G. Pereira
Summary: We study the fracton phase described by the Chamon model in a manifold with a boundary. The new processes and excitations emerging at the boundary can be understood by means of a diagrammatic framework. The continuum theory recovers the gapped boundaries of the lattice model once we include sufficiently strong interactions that break charge conservation. The analysis of the perturbative relevance of the leading interactions reveals a regime in which the Chamon model can have a stable gapless fractonic phase at its boundary.
Article
Quantum Science & Technology
Jielun Chen, E. M. Stoudenmire, Steven R. White
Summary: The quantum Fourier transform (QFT) is an important component of various quantum algorithms, and its entangling power is limited by bit reversal and the decay of Schmidt coefficients. The low entanglement property of the QFT allows for classical simulations and potential speedup over classical fast Fourier transform.
Article
Materials Science, Multidisciplinary
Tim Bauer, Lucas R. D. Freitas, Rodrigo G. Pereira, Reinhold Egger
Summary: We describe the scanning tunneling spectroscopic signatures of Majorana zero modes (MZMs) in Kitaev spin liquids. The tunnel conductance is determined by the dynamical spin correlations of the spin liquid, which we compute exactly, and by spin-anisotropic cotunneling form factors. Near a Z2 vortex, the tunnel conductance exhibits a staircase voltage dependence with conductance steps arising from MZMs and (at higher voltages) from additional vortex configurations. Scanning the probe tip position allows for the detection of vortex locations. Our analysis suggests that topological magnon bound states near defects or magnetic impurities generate spectroscopic signatures that differ qualitatively from those of MZMs.
Article
Materials Science, Multidisciplinary
Moallison F. Cavalcante, Rodrigo G. Pereira, Maria C. O. Aguiar
Summary: We investigate the dynamics of the Kondo effect in a system of two metallic Hubbard chains coupled to a magnetic impurity after a quantum quench. For noninteracting electrons, the charge current across the impurity is determined by a scaling function involving the Kondo time. In the case of interacting electrons, we observe a decrease in the Kondo time with increasing repulsive interaction strength, and the time dependence of the current exhibits characteristics of the Kondo effect in a Luttinger liquid. Our findings emphasize the significance of nonequilibrium dynamics in studying quantum impurities in interacting systems.
Article
Materials Science, Multidisciplinary
Shengtao Jiang, Steven R. White, A. L. Chernyshev
Summary: This study investigates the phase diagram of the quantum S = 1/2 J(1)-J(3) ferro-antiferromagnetic model on the honeycomb lattice and finds that it differs significantly from the classical phase diagram. The introduction of double-zigzag and Ising-z phases as intermediaries between ferromagnetic and zigzag states is observed, extending beyond their classical regions of stability.
Article
Materials Science, Multidisciplinary
Vanuildo S. de Carvalho, Hermann Freire, Rodrigo G. Pereira
Summary: We study a solvable model with bond-directional quadrupolar and octupolar interactions on the honeycomb lattice. This model exhibits a multipolar spin liquid phase and introduces Abelian and non-Abelian topological phases through the breaking of symmetries. Furthermore, our findings reveal the transition from the multipolar spin liquid phase to special ordered phases in the presence of strong integrability-breaking interactions.
Article
Materials Science, Multidisciplinary
Shengtao Jiang, Douglas J. Scalapino, Steven R. White
Summary: In this study, we investigated the pairing properties of the two-dimensional t-t'-t''-J model at a doping level of x approximately 0.1. Our findings show that strong pairing occurs for electron doping when t' > 0, while pairing is absent for hole doping when t' < 0. This is different from the behavior observed in cuprates, where the highest transition temperatures are found for hole doping. Our results suggest that extended hoppings alone are insufficient to explain the pairing in the hole-doped system.
Article
Materials Science, Multidisciplinary
Ryan Pederson, Jielun Chen, Steven R. White, Kieron Burke
Summary: In this paper, we introduce conditional probability (CP) density functional theory (DFT) as a formally exact theory for determining the ground-state energy of a system. By directly calculating CP densities, we eliminate the need for an approximate XC energy functional. Several key properties of the CP density and corresponding CP-KS potential are derived and discussed, with illustrative examples provided to aid understanding. We explore a suitable CP-DFT approximation and discuss exact conditions, limitations, and results for selected examples.
Article
Materials Science, Multidisciplinary
Rafael A. Macedo, Flavia B. Ramos, Rodrigo G. Pereira
Summary: This study focuses on the problem of time-reversal symmetry breaking in quantum spin systems and presents a method to construct one-dimensional anisotropic spin models. It introduces the phenomenon of Landau-forbidden continuous phase transition and provides a concrete example. The results show that the transition between chiral and magnetic phases exhibits an emergent U(1) symmetry, with excitations resembling mobile defects binding fermionic modes.
Article
Materials Science, Multidisciplinary
Chengshu Li, Victor L. Quito, Eduardo Miranda, Rodrigo Pereira, Ian Affleck, Pedro L. S. Lopes
Summary: The proposed extended critical phase with enhanced SU(3) symmetry in spin-2 chains is highly unexpected and indicates an unconventional mechanism for symmetry emergence. The absence of convenient critical points and the usual difficulty in the convergence of numerical methods pose challenges in verifying this hypothetical phase. Through various studies, it is determined that the hypothetical SU(3) spin-2 phase is dominated by ferro-octupolar correlations and does not exhibit Luttinger-liquid-like behavior in correlation functions.
Article
Materials Science, Multidisciplinary
Francesco Buccheri, Alessandro De Martino, Rodrigo G. Pereira, Piet W. Brouwer, Reinhold Egger
Summary: Weyl semimetals possess topological Fermi arc surface states that interact with phonons, which affect the quasiparticle decay rate and conductivity. By solving the Boltzmann equations, we analyze the linear response conductivity dependence on temperature, chemical potential, geometric shape, and slab width. We find an enhanced longitudinal conductivity along the chiral direction at low temperatures and a 1/T^2 scaling behavior at intermediate temperatures.
Article
Materials Science, Multidisciplinary
Randy C. Sawaya, Steven R. White
Summary: The sliced-basis DMRG method is used to construct a low-energy effective Hubbard-like model, and the importance of constraints in the effective Hamiltonian is explored. In addition, the variation of the entanglement entropy for the model's ground state with the range of interactions is studied.
