Higher-order topological insulators and semimetals in generalized Aubry-André-Harper models

Zeng, Qi-Bo; Yang, Yan-Bin; Xu, Yong

doi:10.1103/physrevb.101.241104

Cited by 53 publications

(21 citation statements)

References 99 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The argument can easily be extended to other values of α to ascertain any chiral symmetry connection. Interestingly, very recently, higher-order topological insulators described by AAH potentials have been reported to exhibit a similar chiral symmetry protection of the edge states [58].…”

Section: Topological Edge Statesmentioning

confidence: 93%

Localization, transport and edge states in a two-strand ladder network in an aperiodically staggered magnetic field

Sajid,

Chakrabarti

2020

Preprint

View full text Add to dashboard Cite

We investigate the spectral and transport properties of a two-arm tight-binding ladder perturbed by an external magnetic field following an Aubry-André-Harper profile. The varying magnetic flux trapped in consecutive ladder-cells simulates an axial twist that enables us, in principle, to probe a wide variety of systems ranging from a ribbon Hofstadter geometry to helical DNA chains. We perform an in-depth numerical analysis, using a direct diagonalization of the lattice Hamiltonian to study the electronic spectra and transport properties of the model. We show that such a geometry creates a self-similar multifractal pattern in the energy landscape. The spectral properties are analyzed using the local density of states and a Green's function formalism is employed to obtain the two-terminal transmission probability. With the standard multifractal analysis and the evaluation of inverse participation ratio we show that, the system hosts both critical and extended phase for a slowly varying aperiodic sequence of flux indicating a possible mobility edge. Finally, we report signatures of topological edge modes that are found to be robust against a correlated perturbation given to the nearest neighbor hopping integrals. Our results can be of importance in experiments involving ladder-like quantum networks, realized with cold atoms in an optical trap setup.

show abstract

Section: Topological Edge Statesmentioning

confidence: 93%

Localization, transport and edge states in a two-strand ladder network in an aperiodically staggered magnetic field

Sajid,

Chakrabarti

2020

Preprint

View full text Add to dashboard Cite

show abstract

“…Recently, higher-order topological insulators (TIs) have been theoretically proposed in various systems [41][42][43][44][45][46][47][48], which are characterized by hinge modes in three-dimensional (3D) materials [49][50][51][52] or corner states in two-dimensional (2D) systems [53][54][55][56][57][58][59]. The existence of one-dimensional hinge states has been experimentally confirmed in bismuth [60] and multi-layer WTe 2 [61].…”

Section: Introductionmentioning

confidence: 99%

Transport induced dimer state from topological corner states

Wang

Ren

et al. 2021

Sci. China Phys. Mech. Astron.

View full text Add to dashboard Cite

Recently, a new type of second-order topological insulator has been theoretically proposed by introducing an in-plane Zeeman field into the Kane-Mele model in the two-dimensional honeycomb lattice. A pair of topological corner states arise at the corners with obtuse angles of an isolated diamond-shaped flake. To probe the corner states, we study their transport properties by attaching two leads to the system. Dressed by incoming electrons, the dynamic corner state is very different from its static counterpart. Resonant tunneling through the dressed corner state can occur by tuning the in-plane Zeeman field. At the resonance, the pair of spatially well separated and highly localized corner states can form a dimer state, whose wavefunction extends almost the entire bulk of the diamond-shaped flake. By varying the Zeeman field strength, multiple resonant tunneling events are mediated by the same dimer state. This re-entrance effect can be understood by a simple model. These findings extend our understanding of dynamic aspects of the second-order topological corner states.

show abstract

“…Recent finding of higher-order topological phases opens up a new frontier of physics of higher-order topology [6][7][8][9][10][11][12][13][14][15][16][17][18]. Featured with hinge and corner states for three-and two-dimensional (2D) systems, secondorder topological insulators (SOTIs) with some fantastic applications [19] have been observed in different systems [20][21][22][23][24][25][26][27][28][29].…”

mentioning

confidence: 99%

Engineering exotic second-order topological semimetals by periodic driving

Wang,

Wu,

2021

Preprint

View full text Add to dashboard Cite

Second-order topological semimetals (SOTSMs) is featured with the presence of hinge Fermi arc. How to generate SOTSMs in different systems has attracted much attention. We here propose a scheme to create exotic SOTSMs by periodic driving. It is found that novel Dirac SOTSMs with a widely tunable number of nodes and hinge Fermi arcs, the adjacent nodes with same chirality, and the coexisting nodal points and nodal loops can be generated at ease by the periodic driving. When the time-reversal symmetry is broken, our scheme also permits us to realize an exotic hybrid-order Weyl semimetals with the coexisting hinge and surface Fermi arcs. The multiplicity of the zero-and π/T -mode Weyl points endows our system more colorful 2D sliced topological phases, which can be any combination of normal insulator, Chern insulator, and SOTI, than the static case. Enriching the family of topological semimetals, our scheme supplies a convenient way to artificially synthesize and control exotic topological phases by periodic driving.

show abstract

Higher-order topological insulators and semimetals in generalized Aubry-André-Harper models

Cited by 53 publications

References 99 publications

Localization, transport and edge states in a two-strand ladder network in an aperiodically staggered magnetic field

Localization, transport and edge states in a two-strand ladder network in an aperiodically staggered magnetic field

Transport induced dimer state from topological corner states

Engineering exotic second-order topological semimetals by periodic driving

Contact Info

Product

Resources

About