• 文献标题:   Dispersive sensing of charge states in a bilayer graphene quantum dot
  • 文献类型:   Article
  • 作  者:   BANSZERUS L, MOLLER S, ICKING E, STEINER C, NEUMAIER D, OTTO M, WATANABE K, TANIGUCHI T, VOLK C, STAMPFER C
  • 作者关键词:  
  • 出版物名称:   APPLIED PHYSICS LETTERS
  • ISSN:   0003-6951 EI 1077-3118
  • 通讯作者地址:  
  • 被引频次:   6
  • DOI:   10.1063/5.0040234
  • 出版年:   2021

▎ 摘  要

We demonstrate dispersive readout of individual charge states in a gate-defined few-electron quantum dot in bilayer graphene. We employ a radio frequency reflectometry circuit, where an LC resonator with a resonance frequency close to 280MHz is directly coupled to an Ohmic contact of the quantum dot device. The detection scheme based on changes in the quantum capacitance operates over a wide gate-voltage range and allows us to probe excited states down to the single-electron regime. Crucially, the presented sensing technique avoids the use of an additional, capacitively coupled quantum device such as a quantum point contact or single electron transistor, making dispersive sensing particularly interesting for gate-defined graphene quantum dots.