Abstract
Confirmed in only one-atom-thin layers, charge carriers in graphene exhibit exceptional sensitivity to the electrostatic environments, offering interesting opportunities to quantum transport phenomena by tuning an electrostatic potential profile nearby. Here, we employ designer substrates to engineer quantum transport in graphene via in-situ tunability using gate voltages. Our strategy enables dynamic control of the potential landscape, allowing for the realization of one-dimensional (1D) superlatives and two-dimensional (2D) patterned potentials.
First, using nano-imprinted 1D superlattice, a periodicity of 300nm, we study quantum-Hall transport through PN junction arrays where the quantum-Hall plateaus are quantized at the values determined by the number of the PN junctions and their Landau filling factors. Such highly tunable quantum-Hall plateaus can be used as a resistance standard with arbitrary values. In parallel, the 2D project focuses on both periodic and disordered patterning through the substrate (either SiO2 layer or hBN), aiming to modulate electron scattering processes systematically. Together, these projects expand the experimental toolkit for engineering grapheme’s quantum transport, while providing deeper insights into the interplay between externally imposed potential landscapes and intrinsic electronic properties.
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