Dynamical characterization of Weyl nodes in Floquet Weyl semimetal phases

• URL: http://arxiv.org/abs/2009.09189v2
• Date: Tue, 16 Mar 2021 12:11:51 GMT
• Title: Dynamical characterization of Weyl nodes in Floquet Weyl semimetal phases
• Authors: Muhammad Umer, Raditya Weda Bomantara and Jiangbin Gong
• Abstract summary: We propose a dynamical invariant capable of characterizing and distinguishing between Weyl points at different quasienergy values. This work paves the way for experimentally probing the rich topological band structures of some seemingly simple Floquet semimetal systems.
• Score: 1.5929852667227002
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Due to studies in nonequilibrium (periodically-driven) topological matter, it is now understood that some topological invariants used to classify equilibrium states of matter do not suffice to describe their nonequilibrium counterparts. Indeed, in Floquet systems the additional gap arising from the periodicity of the quasienergy Brillouin zone often leads to unique topological phenomena without equilibrium analogues. In the context of Floquet Weyl semimetal, Weyl points may be induced at both quasienergy zero and $\pi/T$ ($T$ being the driving period) and these two types of Weyl points can be very close to each other in the momentum space. Because of their momentum-space proximity, the chirality of each individual Weyl point may become hard to characterize in both theory and experiments, thus making it challenging to determine the system's overall topology. In this work, inspired by the construction of dynamical winding numbers in Floquet Chern insulators, we propose a dynamical invariant capable of characterizing and distinguishing between Weyl points at different quasienergy values, thus advancing one step further in the topological characterization of Floquet Weyl semimetals. To demonstrate the usefulness of such a dynamical topological invariant, we consider a variant of the periodically kicked Harper model (the very first model in studies of Floquet topological phases) that exhibits many Weyl points, with the number of Weyl points rising unlimitedly with the strength of some system parameters. Furthermore, we investigate the two-terminal transport signature associated with the Weyl points. Theoretical findings of this work pave the way for experimentally probing the rich topological band structures of some seemingly simple Floquet semimetal systems.

Related papers

• Characterizing Floquet topological phases by quench dynamics: A multiple-subsystem approach [11.15439488946414]
  We investigate the dynamical characterization theory for periodically driven systems in which Floquet topology can be fully detected. We propose a more flexible scheme to characterize a generic class of $d$-dimensional Floquet topological phases. This study provides an immediately implementable approach for dynamically classifying Floquet topological phases in ultracold atoms or other quantum simulators.
  arXiv  Detail & Related papers  (2023-10-12T15:23:44Z)
• Wave packet dynamics and edge transport in anomalous Floquet topological phases [0.0]
  An anomalous Floquet topological phase can in general generate more robust chiral edge motion than a Haldane phase. Our results demonstrate that the rich interplay of wave packet dynamics and topological edge states can serve as a versatile tool in ultracold quantum gases in optical lattices.
  arXiv  Detail & Related papers  (2023-02-16T18:45:49Z)
• Slow semiclassical dynamics of a two-dimensional Hubbard model in disorder-free potentials [77.34726150561087]
  We show that introduction of harmonic and spin-dependent linear potentials sufficiently validates fTWA for longer times. In particular, we focus on a finite two-dimensional system and show that at intermediate linear potential strength, the addition of a harmonic potential and spin dependence of the tilt, results in subdiffusive dynamics.
  arXiv  Detail & Related papers  (2022-10-03T16:51:25Z)
• Topological transitions with continuously monitored free fermions [68.8204255655161]
  We show the presence of a topological phase transition that is of a different universality class than that observed in stroboscopic projective circuits. We find that this entanglement transition is well identified by a combination of the bipartite entanglement entropy and the topological entanglement entropy.
  arXiv  Detail & Related papers  (2021-12-17T22:01:54Z)
• Entanglement dynamics of spins using a few complex trajectories [77.34726150561087]
  We consider two spins initially prepared in a product of coherent states and study their entanglement dynamics. We adopt an approach that allowed the derivation of a semiclassical formula for the linear entropy of the reduced density operator.
  arXiv  Detail & Related papers  (2021-08-13T01:44:24Z)
• Light-matter interactions near photonic Weyl points [68.8204255655161]
  Weyl photons appear when two three-dimensional photonic bands with linear dispersion are degenerated at a single momentum point, labeled as Weyl point. We analyze the dynamics of a single quantum emitter coupled to a Weyl photonic bath as a function of its detuning with respect to the Weyl point.
  arXiv  Detail & Related papers  (2020-12-23T18:51:13Z)
• Dual topological characterization of non-Hermitian Floquet phases [0.0]
  We introduce a dual scheme to characterize the topology of non-Hermitian Floquet systems in momentum space and in real space. Our results indicate that a dual characterization of non-Hermitian Floquet topological matter is necessary and also feasible.
  arXiv  Detail & Related papers  (2020-09-28T05:01:28Z)
• Non-Hermitian Floquet phases with even-integer topological invariants in a periodically quenched two-leg ladder [0.0]
  Periodically driven non-Hermitian systems could possess exotic nonequilibrium phases with unique topological, dynamical and transport properties. We introduce an experimentally realizable two-leg ladder model subjecting to both time-periodic quenches and non-Hermitian effects. Our work thus introduces a new type of non-Hermitian Floquet topological matter, and further reveals the richness of topology and dynamics in driven open systems.
  arXiv  Detail & Related papers  (2020-06-16T03:22:53Z)
• Unified theory to characterize Floquet topological phases by quench dynamics [6.496235214212858]
  We propose a unified theory based on quantum quenches to characterize generic $d$-dimensional ($d$D) Floquet topological phases. For a $d$D phase which is initially static and trivial, we introduce the quench dynamics by suddenly turning on the periodic driving. This prediction provides a simple and unified characterization, in which one can not only extract the number of conventional and anomalous Floquet boundary modes, but also identify the topologically protected singularities in the phase bands.
  arXiv  Detail & Related papers  (2020-04-29T08:18:22Z)
• Dynamical solitons and boson fractionalization in cold-atom topological insulators [110.83289076967895]
  We study the $mathbbZ$ Bose-Hubbard model at incommensurate densities. We show how defects in the $mathbbZ$ field can appear in the ground state, connecting different sectors. Using a pumping argument, we show that it survives also for finite interactions.
  arXiv  Detail & Related papers  (2020-03-24T17:31:34Z)
• Bulk detection of time-dependent topological transitions in quenched chiral models [48.7576911714538]
  We show that the winding number of the Hamiltonian eigenstates can be read-out by measuring the mean chiral displacement of a single-particle wavefunction. This implies that the mean chiral displacement can detect the winding number even when the underlying Hamiltonian is quenched between different topological phases.
  arXiv  Detail & Related papers  (2020-01-16T17:44:52Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.