Magnetic-field-induced charge redistribution in disordered graphene double quantum dots

Article

关键词: EXCITED-STATES;   

DOI  :  10.1103/PhysRevB.92.155408

来源: SCIE

【 摘 要 】

We have studied the transport properties of a large graphene double quantum dot under the influence of a background disorder potential and a magnetic field. At low temperatures, the evolution of the charge-stability diagram as a function of the B field is investigated up to 10 T. Our results indicate that the charging energy of the quantum dot is reduced, and hence the effective size of the dot increases at a high magnetic field. We provide an explanation of our results using a tight-binding model, which describes the charge redistribution in a disordered graphene quantum dot via the formation of Landau levels and edge states. Our model suggests that the tunnel barriers separating different electron/hole puddles in a dot become transparent at high B fields, resulting in the charge delocalization and reduced charging energy observed experimentally.

【 授权许可】

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