• There are a number of physical systems with phases described by topologically protected invariants (fractional quantum Hall, topological insulators) but what are the simplest mathematical models that exhibit topological phases? (physicsoverflow.org)
  • For example the toric code that you mention, is a very different kind of topological phase than topological insulators. (physicsoverflow.org)
  • In this paper, based on the lattice model of a topological insulator, we study the quantum phase transitions of topological insulators with different symmetry by calculating their phase diagrams and topological invariants. (epj.org)
  • Topological crystalline insulators are phases of matter where the crystalline symmetries solely protect the topology. (scipost.org)
  • In this work, we explore the effect of many-body interactions in a subclass of topological crystalline insulators, namely the mirror-symmetry protected topological crystalline insulator. (scipost.org)
  • While surface states that are calculated in the framework of a tight-binding model are often called Tamm states, they are suitable to describe also transition metals and insulators. (scholarpedia.org)
  • b occurs in topological insulators and guarantees that the surface bands cross any Fermi level inside the bulk gap. (scholarpedia.org)
  • We find that the hitherto known phase diagrams for this system, derived from the single-particle gap closings, in fact correspond to distinct non-equilibrium phases, which either carry finite currents or are dynamical insulators where particles are entrapped. (mpg.de)
  • We prove that invisible bands associated with zeros of the single-particle Green's function exist ubiquitously at topological interfaces of 2D Chern insulators, dual to the chiral edge/domain-wall modes. (uni-frankfurt.de)
  • Topological photonics mimicking topological insulators has recently attracted considerable attention. (degruyter.com)
  • Exotic properties such as robustness against disorder and spin-locked propagation have been reported, which are similar to those of topological insulators. (degruyter.com)
  • The quasi-localized phase and concomitant topological Anderson transition manifest themselves in the anisotropic transport phenomena of disordered weak topological insulators and nodal-line semimetals, which exhibit the metallic behavior in one direction but the insulating behavior in the other directions. (arxiv.org)
  • Topological insulators and thermoelectric materials. (mpg.de)
  • A design scheme for topological insulators based bonds, bands, symmetry and spin orbit coupling. (mpg.de)
  • Examples of studies range from in-situ investigation of the magnetism of isolated atoms or single molecules, to the properties of oxide materials in thin-film or bulk crystal form, topological insulators, or hybrid ferromagnetic -2D materials such as Graphene. (lu.se)
  • Article{10.21468/SciPostPhysCore.5.4.048, title={{Interaction-driven phase transition in one dimensional mirror-symmetry protected topological insulator}}, author={Devendra Singh Bhakuni and Amrita Ghosh and Eytan Grosfeld}, journal={SciPost Phys. (scipost.org)
  • b, topological insulator. (scholarpedia.org)
  • A topological insulator is a material with time reversal symmetry and topologically protected surface states. (scholarpedia.org)
  • Topological insulator has an energy gap in the bulk interior, just as in an ordinary insulator, but it contains conducting states localized on its surface. (scholarpedia.org)
  • When weak disorder is introduced, we examine the disorder-averaged Bott index and analyze why the anomalous Floquet topological insulator is favored by both uncorrelated and correlated disorder, with the latter having a stronger effect. (uni-frankfurt.de)
  • Here, we explore a single 3-dimensional phononic topological crystalline insulator that simultaneously exhibits a whole family of first-order quadratic surface, second-order hinge, and third-order corner states within the same bandgap. (bvsalud.org)
  • Such a topological crystalline insulator hosting all-order phases originates from the different topological nature when hierarchically projected onto different facets and lower dimensions, thus free from trivial cladding crystals. (bvsalud.org)
  • I guess the Kosterlitz-Thouless transition would be one simple example where the quasi-particles are vortices - i.e. topological defects. (physicsoverflow.org)
  • Topological defects or solitons are irregularities or disruptions that occur within continuous fields or ordered states of matter. (wikipedia.org)
  • For this reason such crystal transitions are called topological defects. (wikipedia.org)
  • Topological defects are not only stable against small perturbations, but cannot decay or be undone or be de-tangled, precisely because there is no continuous transformation that will map them (homotopically) to a uniform or "trivial" solution. (wikipedia.org)
  • The homotopy theory of defects uses the fundamental group of the order parameter space of a medium to discuss the existence, stability and classifications of topological defects in that medium. (wikipedia.org)
  • Poénaru and Toulouse showed that crossing defects get entangled if and only if they are members of separate conjugacy classes of π1(R). Topological defects occur in partial differential equations and are believed[according to whom? (wikipedia.org)
  • false and true topological defects can be distinguished if the defect is in a false vacuum and a true vacuum, respectively. (wikipedia.org)
  • clarification needed] Examples include the soliton or solitary wave which occurs in exactly solvable models, such as screw dislocations in crystalline materials, skyrmion in quantum field theory, and topological defects[clarification needed] of the Wess-Zumino-Witten model. (wikipedia.org)
  • Topological defects in lambda transition universality class[clarification needed] systems including: screw/edge-dislocations in liquid crystals, magnetic flux "tubes" known as fluxons in superconductors, and vortices in superfluids. (wikipedia.org)
  • This project focuses on frontiers of topological matter such as non-Abelian anyons from twists and defects in Moiré heterostructures and topological phenomena in open dissipative systems. (su.se)
  • A key manifestation of topological physics is the presence of edge states which are robust against structural defects or local disorders. (springer.com)
  • The fractionalized mobility of fractons matches the constrained dynamics of the lattice topological defects. (caltech.edu)
  • However, the symmetry of the system plays an important role: different topological quantum phase transitions are protected by different (global) symmetries and then described by different topological invariants. (epj.org)
  • Topological invariants, including the Chern numbers, can topologically classify parameterized Hamiltonians. (uni-frankfurt.de)
  • We find that topological invariants can be properly defined and calculated even if the parameter space is discrete, which is done by geodesic interpolation in the classifying space. (uni-frankfurt.de)
  • We specifically present the interpolation protocol for the Chern numbers, which can be directly generalized to other topological invariants. (uni-frankfurt.de)
  • Particularly, by utilizing the bulk-edge correspondence [ 5 , 6 ], one may investigate different topological phases by probing edge states or edge topological invariants. (springer.com)
  • Topological invariants are routinely computed with reference to crystal momenta - how do we describe them if translational invariance is absent and crystal momenta are no longer defined? (uni-koeln.de)
  • Upon varying the ratio of mass to time-reversal breaking parameter the model undergoes a quantum phase transition from a topologically nontrivial semimetal to a trivial one. (harvard.edu)
  • This is strong evidence for a pressure induced quantum phase transition (QPT) between topological to a trivial electronic state. (uzh.ch)
  • The transition between the two cases is signaled by a discontinuity in the first derivative of the ground state energy and represents a quantum phase transition induced by a special choice of boundary conditions. (irb.hr)
  • Each superconductivity is characterized by the Chem number, and the quantum phase transition is associated with topological changes of the quasiparticle Bloch function in the Brillouin zone. (illinois.edu)
  • We show that by condensing fields that carry both electric charge and magnetic flux of the emergent gauge field, one can obtain spin liquid phases with topological order and no lattice symmetry breaking. (aps.org)
  • In the past decade, the discipline has seen spectacular progress in the research of topological states, phases of matter that are beyond the Landau-Ginzburg-Wilson symmetry-breaking paradigm, but characterized by new types of global quantum numbers. (ucas.ac.cn)
  • In particular, we investigate the symmetry-protected nature of the topological quantum phase transitions: topological quantum phase transitions can not be classified by symmetries. (epj.org)
  • Employing a prototypical mirror-symmetric quasi-one-dimensional model, we demonstrate the emergence of a mirror-symmetry protected topological phase and its robustness in the presence of short-range interactions. (scipost.org)
  • When longer-range interactions are introduced, we find an interaction-induced topological phase transition between the mirror-symmetry protected topological order and a trivial charge density wave. (scipost.org)
  • Interestingly, non-Hermiticity enriches as well as offers unique topological phases considering the interplay between ramified symmetry and topology [3]. (mpg.de)
  • More attention is paid to different tools and techniques necessary for practical applications of the symmetry methods in solid-state problems as molecular dynamics, spectroscopy, electronic bands, phonon spectra, Landau theory of phase transitions. (crystallography.fr)
  • The students will learn how, starting from symmetry requirements, to determine the spectral-transition selection rules with special attention to infrared and Raman spectra. (crystallography.fr)
  • For example, the determination of the order parameter from the knowledge of the initial and final phases, or the enumeration of all symmetry allowed phases that can result from a continuous phase transition. (crystallography.fr)
  • The unifying themes of this work are Hamiltonian dynamics, short-wavelength asymptotics, the classical-quantum correspondence, geometrical and topological methods, and symmetry. (berkeley.edu)
  • We found that the structural stability of the membrane towards NPs is dependent on the topological characteristic of the lipid assembly and of the NPs, where a higher symmetry gave higher stability. (lu.se)
  • In the last several years, there has been a surge of new ideas and methods in theories for these states, and experimental discoveries of topological states of matter have also made great impact. (ucas.ac.cn)
  • This year's Nobel Prize in Physics has been awarded to three physicists, "for theoretical discoveries of topological phase transitions and topological phases of matter. (ieee.org)
  • The Su-Schrieffer-Heeger (SSH) model, which is a fundamental topological system, has been experimentally demonstrated in many photonic systems owing to its simplicity. (degruyter.com)
  • We study quantum phase transitions of three-dimensional disordered systems in the chiral classes (AIII and BDI) with and without weak topological indices. (arxiv.org)
  • We show that the systems with a nontrivial weak topological index universally exhibit an emergent thermodynamic phase where wave functions are delocalized along one spatial direction but exponentially localized in the other two spatial directions, which we call the quasi-localized phase. (arxiv.org)
  • Our extensive numerical study clarifies that the critical exponent of the Anderson transition between the metallic and quasi-localized phases, as well as that between the quasi-localized and localized phases, are different from that with no weak topological index, signaling the new universality classes induced by topology. (arxiv.org)
  • The topological nontrivial semimetal is characterized by the presence of an anomalous Hall effect. (harvard.edu)
  • Just to be clear, I'm talking about phases meaning states of matter, and not just the geometric phase that a wavefunction will pick up under parallel transport in a nontrivial configuration space. (physicsoverflow.org)
  • In this study, we experimentally observed the photonic topological edge states of zigzag plasmonic chains composed of metal nanodiscs in the optical region through far-field imaging. (degruyter.com)
  • Far-field observations serve as an easy and effective tool for the investigation and application of photonic topological edge states. (degruyter.com)
  • a) Photonic topological edge state visualized by a long zigzag chain. (degruyter.com)
  • It is well known that on square lattice N\'eel and valence bond solid states are connected by a continuous phase transition, and the critical theory consists fractionalized spinons and an emergent U(1) gauge field. (aps.org)
  • Motivated by recent numerical works revealing N\'eel and gapped spin liquid states in $J_1$-$J_2$ model on square lattice, we study other phases that can be obtained after destroying the N\'eel order. (aps.org)
  • The band inversion occurs when deforming the honeycomb lattice GPCs, which further leads to the topological band gaps and pseudospin features of the edge states. (springer.com)
  • Here we investigate the robustness problem in a system where edge transmission can survive disorder levels with strengths arbitrarily larger than the bandgap-an anomalous non-reciprocal topological network. (nature.com)
  • We explore the general conditions needed to obtain such an unusual effect in systems made of unitary three-port non-reciprocal scatterers connected by phase links, and establish the superior robustness of anomalous edge transmission modes over Chern ones to phase-link disorder of arbitrarily large values. (nature.com)
  • Among the unique and counter-intuitive attributes of topological systems, topological robustness 1 against disorder and flaws is undoubtedly one of the most remarkable. (nature.com)
  • We find such anomalous robustness in unitary scattering networks made of interconnected non-reciprocal resonant scatterers coupled by non-directed phase links. (nature.com)
  • We compare quantitatively the robustness of transmission through the anomalous and Chern channels to phase-link and scattering disorder, by statistical averaging over many disorder realizations. (nature.com)
  • Topological solitons arise with ease when creating the crystalline semiconductors used in modern electronics, and in that context their effects are almost always deleterious. (wikipedia.org)
  • We present a holographic model of a topological Weyl semimetal. (harvard.edu)
  • Josephson diode effect from Cooper pair momentum in a topological semimetal. (nature.com)
  • But on further research it seems that is the physics of the XY phase which you've already mentioned. (physicsoverflow.org)
  • The study of phases of matter is a central theme in physics, and has been evolving in parallel with our improved understanding, via new concepts and methods, of many-body systems. (ucas.ac.cn)
  • In mathematics and physics, a topological soliton or a topological defect is a solution of a system of partial differential equations or of a quantum field theory homotopically distinct from the vacuum solution. (wikipedia.org)
  • phase transitions in condensed matter physics. (wikipedia.org)
  • Using a variety of analytical and numerical methods we develop a theoretical understanding of the various phases and their transitions, and uncover the rich interplay of non-equilibrium many-body physics, quantum entanglement and topology in a simple looking, yet a rich model system. (mpg.de)
  • The physics of topological phases of matter has become one of the most exciting fields of modern physics. (uni-koeln.de)
  • And how do we understand the physics of topological phase transitions driven by disorder? (uni-koeln.de)
  • Adopting the hypothesis about the exact cancellation of vacuum condensates contributions to the ground state energy in particle physics to the leading order in graviton-mediated interactions, we argue that the observable cosmological constant can be dynamically induced by an uncompen- sated quantum gravity correction to them after the QCD phase transition epoch. (lu.se)
  • The method is explored on a set of synthetic dealt with in a straightforward way using ``stan- problems, which are generated to resemble two dard'' ANN energy functions similar to those en- real-world problems representing long and medi- countered in spin physics. (lu.se)
  • The results can be interpreted in terms of the holographic renormalization group (RG) flow leading to restoration of time reversal at the end point of the RG flow in the trivial phase. (harvard.edu)
  • The polarization dependence of edge-state imaging showed switching of the systems in trivial and topological phases in the same zigzag chain. (degruyter.com)
  • Depending on the balance between t 1 and t 2 , the system exhibits a trivial or topological phase. (degruyter.com)
  • We use dynamical domain wall fermion configurations on lattices of size 32^3x8, used earlier in [1] to calculate the crossover transition temperature Tc in QCD, and detect the topological structures through the zero modes of the overlap operator. (fnal.gov)
  • We verify this statement in a repulsive Hubbard model with a topological flat band, using real-space dynamical mean-field theory to study the domain walls of its ferromagnetic ground state. (uni-frankfurt.de)
  • When skyrmions move faster, the large self-induced deformation triggers topological transitions. (uai.cl)
  • These transitions are characterized by the proliferation of skyrmions and a different total topological charge, which is obtained as a function of the skyrmion velocity. (uai.cl)
  • Furthermore, such motion-induced topological phase transitions make it possible to control the number of ferromagnetic skyrmions through velocity effects. (uai.cl)
  • Using a minimal theoretical model, we can then link the sign reversal of the inductance magnetochiral anisotropy to the so-called 0−π-like transition, a predicted but still elusive feature of multichannel junctions. (nature.com)
  • Indeed, in the last two decades there have been many parallel outcomes in the theoretical aspects of description and analysis of periodic structures (nets, tilings, surfaces, etc.), in the elaboration of databases, and in the development of software for analyzing and describing (illustrating) topological aspects of both real crystal structures and theoretical extended architectures. (crystallography.fr)
  • Several superconducting families are widely studied at Institut Néel: Cuprates, Nickelates, iron based superconductors, heavy fermions, transition metal dichalcogneides… All these families open new fundamental questions and experimental and theoretical challenges. (cnrs.fr)
  • I study topics related to quantum phase transitions, superconductivity, and nanotechnology. (usc.edu)
  • Recently, we have applied the stochastic series expansion algorithm to study field induced phase transitions in quantum spin liquids, developed optimization algorithms to construct nano-scale opto-electronic devices, and generalized the BCS (Bardeen-Cooper-Schrieffer) theory to investigate the consequences of unconventional superconductivity in strongly correlated materials. (usc.edu)
  • The high Tc superconductivity in the copper oxides compounds pushes the community to look for superconductivity in other oxides with another transition metal. (cnrs.fr)
  • Topics of particular current interest include the interplay between charge, orbital, and spin degrees of freedom in transition metal oxides, the mechanism of high-temperature superconductivity, and the control of electronic phase behavior in metal-oxide superlattices. (mpg.de)
  • We investigate theoretically in Bernal-stacked bilayer graphene system the effect of the trigonal warping, which stems from the interlayer hopping, upon distinctive topological phases, such as the quantum anomalous Hall effect as well as the quantum valley Hall effect. (aps.org)
  • These extraordinary properties make graphene an ideal candidate to the all-integrated topological plasmonic components. (springer.com)
  • Here we demonstrate an anomalous non-reciprocal topological phase in which edge transmission is quantitatively stronger than for the Chern phase, surviving parametric fluctuations arbitrarily larger than the bandgap size. (nature.com)
  • In the topological phase of photonic SSH systems, topological edge states appear as electromagnetic states localized at the edge of the chain with a frequency inside the bandgap. (degruyter.com)
  • Especially in helimagnets with short magnetic periods, the geometrical or topological Hall effect can dominate Hall resistivity profile [2]. (mrs.org)
  • To date, the far-field imaging of topological edge states in plasmonic chains has not been reported because of the constraint imposed by the diffraction limit. (degruyter.com)
  • When the skyrmion dynamics beyond the particle-like description is considered, this topological structure can deform due to a self-induced field. (uai.cl)
  • I wil discuss our use of coherent X-ray scattering in the stripe and skyrmion phase to obtain speckle patterns that can be used to determine domain cascades and avalanches. (lu.se)
  • Using existing framework of statistical mechanics we were able to extract scaling laws for the avalanches in the stripe and skyrmion phases. (lu.se)
  • The presence of the trigonal warping terms shrinks the phase space of quantum anomalous/valley Hall effect and leads to the emergence of the valley-polarized quantum anomalous Hall effect with high Chern numbers ranging from C $=$ -7 to 7. (aps.org)
  • We confirm experimentally the exceptional resilience of the anomalous phase, and demonstrate its operation in various arbitrarily shaped disordered multi-port prototypes. (nature.com)
  • Our systematic characterizations of the structure and SC properties associated with the topological QPT provide deep insight into the pressure induced phase diagram in this topological quantum material. (uzh.ch)
  • I'm looking for simple models where one can make a phase diagram, and as a function of the available couplings there is a change in some topological property of the system. (physicsoverflow.org)
  • In the absence of disorder, we determine the phase diagram and identify a new phase characterized by edge states with alternating chirality in adjacent gaps. (uni-frankfurt.de)
  • I think you need to define what you mean by a "topological state of matter", since the term is used in several inequivalent ways. (physicsoverflow.org)
  • No matter how complex the context, anything that qualifies as a topological soliton must at some level exhibit this same simple issue of reconciliation seen in the twisted phone cord example. (wikipedia.org)
  • Stimulated by the discovery of topological phases of matter, fields that utilize the topological nature of systems have attracted considerable research attention. (degruyter.com)
  • Our group explores the properties of topological quantum matter under the real life condition that translational invariance is broken by material imperfections and disorder. (uni-koeln.de)
  • We report our study on the properties of the topological structures present in the QCD medium just above the chiral crossover transition. (fnal.gov)
  • Disorder-induced cubic phase in Fe 2 -based Heusler alloys. (mpg.de)
  • Looking at finite-sized systems, we further modulate the boundary to uncover the topological features in such steady states - in particular the emergence of leaky boundary modes. (mpg.de)
  • Our work provides deeper insight into interacting topological systems. (uni-frankfurt.de)
  • We investigate microscopic models of interacting electronic systems, and use numerical techniques, such as Quantum Monte Carlo, Renormalization Group and Exact Diagonalization, to find their phase diagrams, ground state properties, and excitation spectra. (usc.edu)
  • My research group investigates microscopic models of interacting electronic systems, using numerical techniques such as Quantum Monte Carlo, to understand their phase diagrams, thermodynamic properties, and excitation spectra. (usc.edu)
  • Examples of such systems currently under investigation are polynuclear transition metal clusters, and in the solid-state, cuprates and nickelates. (mpg.de)
  • For the superconducting case, the Chem number has several equivalent but different topological expressions given by vortices, the Dirac monopole, and strings. (illinois.edu)
  • When only the dominant interaction is antiferromagnetic, and thus induces topological frustration, the standard antiferromagnetic order (expressed by the magnetization) is destroyed. (irb.hr)
  • Large resistivity change and phase transition in the antiferromagnetic semiconductors LiMnAs and LaOMnAs. (mpg.de)
  • Topological phase transition in bulk materials described by the coherent potential approximation technique. (mpg.de)
  • Tunability of the electronic properties of two-dimensional bilayer hetero structures of transition-metal dichalcogenides (i.e. (osti.gov)
  • The exotic material properties make topological states an ideal platform for quantum computation and other technical applications. (ucas.ac.cn)
  • We demonstrate quantum phase transitions by these topological quantities both for singlet and triplet cases. (illinois.edu)
  • We find that the trigonal warping plays a vital part in the formation of topological phases in large exchange field and/or interlayer potential difference by changing Chern numbers. (aps.org)
  • This behaviour inherently confines the topological protection of Chern phases to small distributed disorder levels. (nature.com)
  • The existence of a topological defect can be demonstrated whenever the boundary conditions entail the existence of homotopically distinct solutions. (wikipedia.org)
  • Topological states host many a fascinating phenomenon such as robust edge states and fractional excitations. (ucas.ac.cn)
  • Classical-wave topological materials lacking intrinsic half-integer spins are less robust while more tunable. (bvsalud.org)
  • Quantum disorder and chaos generate a multitude of phenomena including strong quantum fluctuations in observables, single and many particle quantum localization, and various types of unique quantum phase transitions. (uni-koeln.de)
  • The appearance of complex eigen-spectra requires us to restructure the framework for characterising the many body phases in a non-Hermitian system. (mpg.de)
  • The scientific objective of this RAC consortium is to use advanced X-ray methods in order to study the dynamics of proteins in crowded environments, in condensates and during phase transitions on their relevant length and time scales. (su.se)
  • Therefore, we propose connected chains and investigate the effect of the shape of the connected part, which reveals that similar topological edge states can be obtained even in the connected chains. (degruyter.com)
  • One of the simplest and most commonplace examples of a topological soliton occurs in old-fashioned coiled telephone handset cords, which are usually coiled clockwise. (wikipedia.org)