Quantum dots coupled to superconducting impedance matching circuits / Dirac semimetal nanowires

From QCLab
Dr. Jung, Minkyung (DGIST)


As the first part of my talk, I will briefly introduce hybrid devices of superconducting cavities and quantum dot devices. Superconducting coupling carbon nanotube devices to microwave circuits offers a significant increase in bandwidth and signal-to-noise ratio. These facilitate fast non-invasive readouts important for quantum optics, shot noise and correlation measurements. Here, we successfully couple a carbon nanotube (CNT) double quantum dot to a GHz superconducting matching circuit using a mechanical transfer technique. The device shows a tunable bipolar double dot behavior, reaching the few-electron/hole regime. The resonance response reflected by the matching circuit is a sensitive probe of the charge state of the device, allowing a determination of the absolute charge number. The resonance response at the interdot charge transitions enables quantitative parameter extraction. Presented results open the path for novel studies of microwave photons interacting with electrons in carbon nanotubes. Secondly, I will talk about my recent data on quantum transport measurements of Dirac semimetal nanowires.