Vortex of beam shift induced by mono-chiral interface states

Yang, Meijun; Hou, Quan-Teng; Wang, Rui-Qiang

doi:10.1088/1367-2630/ab753b

Cited by 10 publications

(2 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The ultrahigh mobility and spectacular transport properties of the charged Weyl fermions can find applications in high-speed electronic circuits and computers [14][15][16]. Motivated both by the interesting physics and potential applications, WSMs have recently spurred intensive and innovative research in the field of condensed-matter physics [17][18][19][20][21][22][23][24].…”

Section: Introductionmentioning

confidence: 99%

Chiral-anomaly-induced angular narrowing of the positive longitudinal magnetoconductivity in Weyl semimetals

Deng

et al. 2020

Phys. Rev. Research

Self Cite

View full text Add to dashboard Cite

By generalizing the Landau quantization Boltzmann equation to a finite-size system, we investigate the magnetotransport in disordered Weyl semimetals (WSMs) for both the ballistic and diffusive regimes. It is found that, in the diffusive limit, the chiral chemical potential would drive extra electrical current to flow through the chiral channels in the n = 0 Landau levels, leading to emergence of the positive longitudinal magnetoconductivity (LMC). The positive LMC will exhibit the angular narrowing phenomenon ifhω c E F √ l a /l e , where ω c , E F , and l a(e) denote, respectively, the cyclotron frequency, the Fermi energy, and the intravalley (intervalley) relaxation length. The anomalous magnetic field dependence of the angular narrowing, i.e., the width and height of the positive LMC peak could increase or decrease with increasing the magnetic field, can be attributable to quantum oscillations of the chiral anomaly. In addition, the quantum oscillations are sensitive to the temperature and impurity scattering, which may also cause some other anomalous properties for the LMC. Our findings are helpful to understand the anomalous behaviors of the positive LMC in WSMs.

show abstract

Section: Introductionmentioning

confidence: 99%

Chiral-anomaly-induced angular narrowing of the positive longitudinal magnetoconductivity in Weyl semimetals

Deng

et al. 2020

Phys. Rev. Research

Self Cite

View full text Add to dashboard Cite

show abstract

“…The possibility to manipulate electron beams in graphene by means of pn junctions or elastic deformations has lead to various proposals for nano-electronic devices, such as Veselago lenses [4,6,[29][30][31][32][33][34][35], electron fiber optics [3,36], interferometers [37,38], valley beam splitters [7,26,[39][40][41][42][43][44][45][46][47][48][49][50], collimators [51,52], switches [53], reflectors [54,55], transistors [2,56,57], and Dirac fermions microscopes [58]. Electron optics has been extended recently from graphene to other materials, such as phosphorene where negative reflection has been pre-dicted [59,60], non-coplanar refraction and Veselago lenses in Weyl semi-metals [61][62][63][64], anomalous caustics in borophene pn junctions [65], and super-diverging lenses in Dirac materials [30].…”

Section: Introductionmentioning

confidence: 99%

Gradient-index electron optics in graphene pn junctions

Paredes-Rocha,

Betancur-Ocampo,

Szpak

et al. 2020

Preprint

View full text Add to dashboard Cite

We investigate the electron transport in smooth graphene pn junctions, generated by gradually varying electrostatic potentials. The numerically calculated coherent current flow patterns can be understood largely in terms of semi-classical trajectories, equivalent to the ones obtained for light beams in a medium with a gradually changing refractive index. In smooth junctions, energetically forbidden regions emerge, which increase reflections and can generate pronounced interference patterns, for example, whispering gallery modes. The investigated devices do not only demonstrate the feasibility of the gradient-index electron optics in graphene pn junctions, such as Luneburg and Maxwell lenses, but may have also technological applications, for example, as electron beam splitters, focusers and waveguides. The semi-classical trajectories offer an efficient tool to estimate the current flow paths in such nano-electronic devices.

show abstract

Negative group delay of reflected Weyl quasiparticles

Yang

Wang

2021

New J. Phys.

View full text Add to dashboard Cite

When an electron is incident from a Weyl material to an insulator and totally reflected, it suffers a reflection group delay and a reflection shift (Goos–Hänchen and/or Imbert–Fedorov shifts). We found the group delay is negative for half of the incident states. The negative group delay does not mean the electron is bounced back before its injection, but is an effective acceleration of the electron near the interface induced by self-interference. The reflection shift orients circulating the points at which the surface-bulk state transition occurs. The reflection shift and the group delay cause velocity correction of the bound states in the Weyl material sandwiched by two insulators. The velocity correction features induced by the negative group delay were verified by a tight-binding calculation, in which the concept of group delay is not used.

show abstract

Vortex of beam shift induced by mono-chiral interface states

Cited by 10 publications

References 36 publications

Chiral-anomaly-induced angular narrowing of the positive longitudinal magnetoconductivity in Weyl semimetals

Chiral-anomaly-induced angular narrowing of the positive longitudinal magnetoconductivity in Weyl semimetals

Gradient-index electron optics in graphene pn junctions

Negative group delay of reflected Weyl quasiparticles

Contact Info

Product

Resources

About