128th RQC Seminar

• 講演者

  Mr. András Márton Gunyhó
  (Department of Applied Physics, Aalto University )

• 日程

  2024年8月21日（水） 13:00-14:00

• 開催場所

  ハイブリッド（ZOOM・ 和光地区 C61 統合支援施設 2階 大会議室）

• 講演タイトル

  Superconducting qubit readout using a thermal detector

• お問合せ

  rqc_info[at]ml.riken.jp

講演概要
Currently, state-of-the-art high-fidelity single-shot readout of superconducting qubits relies on parametric amplifiers at the millikelvin stage. However, scaling parametric amplifiers beyond hundreds of qubits is challenging due to practical size and power limitations. In this work, we utilize an ultrasensitive thermal detector, a so-called nanobolometer, in place of a parametric amplifier to perform qubit readout. Such bolometers have several properties that are advantageous for scalability. In an initial proof of concept experiment, we achieve single-shot readout with a fidelity of 1 - P(g|e) - P(e|g) = 0.618 with a readout duration of 13.9µs. In addition to single-shot readout, I will present preliminary results on multiplexed readout using multiple bolometers on the same chip, and a clear pathway to increasing the readout fidelity to the level of 0.999 with an integration time on the order of 100 nanoseconds.