We present microwave frequency measurements of the dynamic admittance of a quantum dot tunnel coupled to a two-dimensional electron gas. The measurements are made via a high-quality 6.75 GHz on-chip resonator capacitively coupled to the dot. The resonator frequency is found to shift both down and up close to conductance resonance of the dot corresponding to a change of sign of the reactance of the system from capacitive to inductive. The observations are consistent with a scattering matrix model. The sign of the reactance depends on the detuning of the dot from conductance resonance and on the magnitude of the tunnel rate to the lead with respect to the resonator frequency. Inductive response is observed on a conductance resonance, when tunnel coupling and temperature are sufficiently small compared to the resonator frequency.
On-chip superconducting GHz RF reflectometry of the capacitance response in bilayer graphene
DGIST Research Institute, DGIST(大邱冈科学技术院研究院);Department of Physics and Chemistry, DGIST(大邱冈科学技术院物理化学系);Quantum Technology Institute, Korea Research Institute of Standards and Science(韩国标准科学研究院量子技术研究所);Industrial AX Innovation Research Institute and Sensor Technology Support Center, DGIST(大邱冈科学技术院工业AX创新研究所和传感器技术支持中心);Research Center for Materials Nanoarchitectonics, National Institute for Materials Science(物质材料研究机构材料纳米结构研究中心);Research Center for Electronic and Optical Materials, National Institute for Materials Science(物质材料研究机构电子光学材料研究中心);Department of Physics, Kyungpook National University(庆北大学物理系);Department of Interdisciplinary Engineering, DGIST(大邱冈科学技术院交叉工程系)
Max Planck Institute for the Structure and Dynamics of Matter(马克斯·普朗克物质与结构动态研究所);Center for Free-Electron Laser Science (CFEL)(自由电子激光科学中心);Max Planck Institute for the Physics of Complex Systems(马克斯·普朗克复杂系统物理研究所);Department of Physics, Columbia University(哥伦比亚大学物理系)
Reflections on Quantum Reflectometry: Quantum and Tunneling capacitances as well as Sisyphus and Hermes resistances
B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine(乌克兰国家科学院B.维尔金低温物理与工程研究所);V. N. Karazin Kharkiv National University(哈尔科夫国立大学);Department of Mathematics, Kyiv School of Economics(基辅经济学院数学系);Quantum Motion(量子运动公司);Cavendish Laboratory, University of Cambridge(剑桥大学卡文迪许实验室);Quantum Computing Center, RIKEN(理研量子计算中心);Physics Department, The University of Michigan(密歇根大学物理系)