Topologically protected interface phonons in two-dimensional nanomaterials: hexagonal boron nitride and silicon carbide.

@article{Jiang2018TopologicallyPI,
  title={Topologically protected interface phonons in two-dimensional nanomaterials: hexagonal boron nitride and silicon carbide.},
  author={Jin-Wu Jiang and Bingshen Wang and Harold S Park},
  journal={Nanoscale},
  year={2018},
  volume={10 29},
  pages={
          13913-13923
        }
}
We perform both lattice dynamics analysis and molecular dynamics simulations to demonstrate the existence of topologically protected phonon modes in two-dimensional, monolayer hexagonal boron nitride and silicon carbide sheets. The topological phonon modes are found to be localized at an in-plane interface that divides these systems into two regions of distinct valley Chern numbers. The dispersion of this topological phonon mode crosses over the frequency gap, which is opened through analogy… 

YOU MAY BE INTERESTED IN Strain tunable phononic topological bandgaps in two-dimensional hexagonal boron nitride

Topological insulators (TIs) have recently received significant attention due to the promise of lossless transport of various types of energy. Despite this interest, one outstanding issue is that the

Tunable topological bandgaps and frequencies in a pre-stressed soft phononic crystal

Topological insulators (TIs) have recently received significant attention due to the promise of lossless transport of various types of energy. Despite this interest, one outstanding issue is that the

Topological chiral phonons along the line defect of intralayer heterojunctions

As a potential degree of freedom, the chirality of phonons is expected to become a carrier of information. Exploring the phonon mode that can stably maintain chirality along a certain transport path

Topological effects of phonons in GaN and AlGaN: A potential perspective for tuning phonon transport

Tuning thermal transport in semiconductor nanostructures is of great significance for thermal management in information and power electronics. With excellent transport properties, such as ballistic

Double Dirac cones and topologically nontrivial phonons for continuous square symmetric C4(v) and C2(v) unit cells

Because phononic topological insulators have primarily been studied in discrete, graphene-like structures with C$_{6}$ or C$_{3}$ hexagonal symmetry, an open question is how to systematically achieve

Valley-dependent topologically protected elastic waves using continuous graphene membranes on patterned substrates.

TLDR
This work presents a novel structure for topologically protected propagation of mechanical waves in a continuous, elastic membrane using an analog of the quantum valley Hall effect that is robust against imperfections, is immune to backscattering losses, and supports topologically-protected wave propagation along all available paths and angles.

Exploring the structure-property relationship of three-dimensional hexagonal boron nitride aerogels with gyroid surfaces.

TLDR
A binary phase-field crystal (PFC) model is employed to construct the atomic structures of hBNAGs, upon which the mechanical and thermal behaviors of h BNAGs were systematically investigated using large-scale atomistic simulations, providing a deep understanding of the structure-property relationships.

Recent advances in topological elastic metamaterials

TLDR
This paper provides a comprehensive overview of the flourishing research frontier on topological elastic metamaterials, and highlights prominent future directions in this field including three-dimensional elastic topological phases and higher-order topological insulators.

Tutorial: Computing Topological Invariants in 2D Photonic Crystals

The field of topological photonics emerged as one of the most promising areas for applications in transformative technologies: possible applications are in topological lasers or quantum optics

References

SHOWING 1-10 OF 81 REFERENCES

Tunable topological phononic crystals

Topological insulators, first observed in electronic systems, have inspired many analogues in photonic and phononic crystals in which remarkable one-way propagation edge states are supported by

Topologically protected elastic waves in phononic metamaterials

TLDR
Numerically a phononic topological metamaterial is demonstrated in an elastic-wave analogue of the quantum spin Hall effect, demonstrating topological protection for phonons in both static and time-dependent regimes.

Design and experimental observation of valley-Hall edge states in diatomic-graphene-like elastic waveguides

We report on the design and experimental validation of a two-dimensional phononic elastic waveguide exhibiting topological valley-Hall edge states. The lattice structure of the waveguide is inspired

Helical edge states and topological phase transitions in phononic systems using bi-layered lattices

We propose a framework to realize helical edge states in phononic systems using two identical lattices with interlayer couplings between them. A methodology is presented to systematically transform a

Topological Phononic Crystals with One-Way Elastic Edge Waves.

TLDR
A new type of phononic crystals with topologically nontrivial band gaps for both longitudinal and transverse polarizations, resulting in protected one-way elastic edge waves, which could potentially lead to the design of a novel class of surface wave devices that are widely used in electronics, telecommunication, and acoustic imaging.

Phonon analog of topological nodal semimetals

Topological band structures in electronic systems like topological insulators and semimetals give rise to highly unusual physical properties. Analogous topological effects have also been discussed in

Valley Chern numbers and boundary modes in gapped bilayer graphene

TLDR
The important role played by intervalley coupling effects not directly captured by the continuum model is addressed using lattice calculations for specific domain wall structures.

Topological Phonon Modes in a Two-Dimensional Wigner Crystal

We investigate the spin–orbit coupling effect in a two-dimensional (2D) Wigner crystal. It is shown that sufficiently strong spin–orbit coupling and an appropriate sign of g-factor could transform

Edge waves in plates with resonators: an elastic analogue of the quantum valley Hall effect

We investigate elastic periodic structures characterized by topologically nontrivial bandgaps supporting backscattering suppressed edge waves. These edge waves are topologically protected and are

Predicting Two-Dimensional Silicon Carbide Monolayers.

TLDR
The findings suggest that the 2D SixC1-x monolayers may present a new "family" of 2D materials, with a rich variety of properties for applications in electronics and optoelectronics.
...