Particle–hole symmetry protects spin-valley blockade in graphene quantum dots

L. Banszerus, S. Möller, K. Hecker, E. Icking, K. Watanabe, T. Taniguchi, F. Hassler, C. Volk and C. Stampfer ()
Additional contact information
L. Banszerus: RWTH Aachen University
S. Möller: RWTH Aachen University
K. Hecker: RWTH Aachen University
E. Icking: RWTH Aachen University
K. Watanabe: National Institute for Materials Science
T. Taniguchi: National Institute for Materials Science
F. Hassler: RWTH Aachen University
C. Volk: RWTH Aachen University
C. Stampfer: RWTH Aachen University

Nature, 2023, vol. 618, issue 7963, 51-56

Abstract: Abstract Particle–hole symmetry plays an important role in the characterization of topological phases in solid-state systems1. It is found, for example, in free-fermion systems at half filling and it is closely related to the notion of antiparticles in relativistic field theories2. In the low-energy limit, graphene is a prime example of a gapless particle–hole symmetric system described by an effective Dirac equation3,4 in which topological phases can be understood by studying ways to open a gap by preserving (or breaking) symmetries5,6. An important example is the intrinsic Kane–Mele spin-orbit gap of graphene, which leads to a lifting of the spin-valley degeneracy and renders graphene a topological insulator in a quantum spin Hall phase7 while preserving particle–hole symmetry. Here we show that bilayer graphene allows the realization of electron–hole double quantum dots that exhibit near-perfect particle–hole symmetry, in which transport occurs via the creation and annihilation of single electron–hole pairs with opposite quantum numbers. Moreover, we show that particle–hole symmetric spin and valley textures lead to a protected single-particle spin-valley blockade. The latter will allow robust spin-to-charge and valley-to-charge conversion, which are essential for the operation of spin and valley qubits.

Date: 2023
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/s41586-023-05953-5 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:618:y:2023:i:7963:d:10.1038_s41586-023-05953-5

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/s41586-023-05953-5

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().