# Easy-to-configure zero-dimensional valley-chiral modes in a graphene point junction

https://mdr.nims.go.jp/datasets/fbc32dfa-7ca7-41be-8f8f-69798009f7fb

## File

- [sciadv.adp6296.pdf](https://mdr.nims.go.jp/filesets/68cd04fa-67b3-48b4-a8cc-7788a91f64f2/download) ([Detail](https://mdr.nims.go.jp/filesets/68cd04fa-67b3-48b4-a8cc-7788a91f64f2.md))

## Id

fbc32dfa-7ca7-41be-8f8f-69798009f7fb

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2025-02-18T01:00:50.342097Z

## Updated at

2025-02-23T13:46:21.261034Z

## Published at

2025-02-23T13:46:21.357630Z

## Doi



## First published url

https://doi.org/10.1126/sciadv.adp6296

## Date published

2024-09-13

## Recorded date published

2024-9-13

## Resource type

journal_article

## Manuscript type

vor

## Collection



## Title

- title: Easy-to-configure zero-dimensional valley-chiral modes in a graphene point
    junction
  title_type: original
  lang: en

## Description

- description: The band edges of typical 2D semimetals and semiconductors are found
    at two corners of the first Brillouin zones, commonly referred to as K and K’
    valleys. Efforts have been made in initiating valley-polarized current (valleytronics)
    for low-dissipation quantum electronics, akin to that of spintronics. In monolayer
    transition metal dichalcogenides, dynamic valley polarization can be achieved
    with optical excitations. At a 1D boundary of two bilayer graphene domains (natural
    or gate-defined), topological valley-chiral states can be realized by electrostatics
    alone. However, the demanding fabrication requirements limit device reproducibility
    and controllability, and therefore scalability towards larger scale valleytronics
    circuits with more advanced functionality.  In this work, we develop a new device
    architecture of point junction that addresses these device limitations. A PN junction
    and a quantum point contact20,21 is simultaneously defined at the center of the
    device, where valley-chiral states can be easily configured and switched on/off
    with high device yield. With valley chirality tuned on/off, we characterize a
    valley polarization of ~80% at zero magnetic field. By eliminating unintended
    scattering centers, we demonstrate Shubnikov–de Haas (SdH) oscillation via valley-chiral
    modes under finite magnetic field, with ballistic dip resistances at expected
    quantization of 4e2/h. The easy-to-configure valley-chiral states provide a new
    platform to study valley-polarized quantum phenomena in graphene and paves a path
    towards scalable valleytronics.
  description_type: abstract
  lang: und

## Creator

- name: Konstantin Davydov
  role: author
- name: Xi Zhang
  role: author
- name: Wei Ren
  role: author
- name: Matthew Coles
  role: author
- name: Logan Kline
  role: author
- name: Bryan Zucker
  role: author
- name: Kenji Watanabe
  role: author
  orcid: https://orcid.org/0000-0003-3701-8119
  organization: National Institute for Materials Science
  ror: https://ror.org/026v1ze26
- name: Takashi Taniguchi
  role: author
  orcid: https://orcid.org/0000-0002-1467-3105
  organization: National Institute for Materials Science
  ror: https://ror.org/026v1ze26
- name: Ke Wang
  role: author

## Contact agent



## Publisher

organization: American Association for the Advancement of Science (AAAS)

## Managing organization



## Keyword

- subject: Valleytronics
  schema: not_defined
- subject: bilayer graphene
  schema: not_defined
- subject: valley-polarized current
  schema: not_defined

## Rights

- identifier: https://creativecommons.org/licenses/by/4.0/

## Other identifier(s)



## Data origin

- data_origin_type: other

## Embargo



## Journal

- title: Science Advances
  issn: '23752548'
  volume: '10'
  issue: '37'
  article_number: eadp6296

## Conference



## Related item



## Funding



## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



## Software



## Custom property



## Fileset

- id: 68cd04fa-67b3-48b4-a8cc-7788a91f64f2
  filename: sciadv.adp6296.pdf
  content_type: application/pdf
  size: 4003651
  md5: 25b00bc1e7f756bc525f073b543ef342

## Thumbnail

fileset_id: 68cd04fa-67b3-48b4-a8cc-7788a91f64f2
filename: sciadv.adp6296.pdf