Graphene electron metasurfaces realized using one-dimensional array of quantum dots with gradient-varying radii

doi:10.3969/j.issn.1000-5641.2025.03.013

Abstract

Abstract:

We theoretically demonstrate a novel metasurface for graphene ballistic electrons, which is a one-dimensional gate-defined quantum-dot array comprising multiple complex unit cells arranged periodically. Each complex unit cell is composed of a set of quantum dots with gradient-varying radii. The same bias is applied to all the quantum dots. The rigorous Mie scattering theory and multiple scattering theory reveal that the metasurfaces comprising different complex unit cells can deflect the incident electron wave at different angles with almost 100% efficiency, thus demonstrating high control over the transport of graphene electrons. The ultracompactness of the metasurface enables it to shape the wavefront within a distance significantly smaller than the room-temperature ballistic-transport distance. Electron optics devices can be miniaturized considerably by adopting the metasurface, thus providing a solution for eliminating low-temperature conditions and developing room-temperature electron optics technologies with significant application potential in graphene.

Key words: Dirac fermion, quantum dot array, multiple scattering theory, electron metasurfaces

CLC Number:

O412

Xin TONG, Junjie DU. Graphene electron metasurfaces realized using one-dimensional array of quantum dots with gradient-varying radii[J]. J* E* C* N* U* N* S*, 2025, 2025(3): 109-115.

Figures/Tables 4

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$\varGamma$/nm	${\theta }_{\rm{actu}}$/(°)	${\theta }_{\rm{calc}}$/(°)
96	40.6	40.5
120	31.1	31.6
144	25.8	25.9
168	21.0	22.0
192	18.9	19.1
216	17.4	16.2

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