RQC Seminar

25th RQC Seminar

• Speaker

  Dr. Xianjing Zhou
  (RQC, Floating-Electron-Based Quantum Information RIKEN Hakubi Research Team)

• Date

  13:00-14:30 (JST), January 31, 2023 (Tuesday)

• Venue

  Hybrid (Zoom / Wako Welfare and Conf. 2F Large Meeting Room RIKEN Wako branch)

• Title

  Single electrons on solid neon: a new solid-state qubit platform with ultralong coherence

• Inquiries

  rqc_info[at]ml.riken.jp

Abstract
Progress towards the realization of quantum computers requires persistent advances in their constituent building blocks—qubits. Novel qubit platforms that simultaneously embody long coherence, fast operation and large scalability offer compelling advantages in the construction of quantum computers and many other quantum information systems. Electrons, ubiquitous elementary particles of non-zero charge, spin and mass, have commonly been perceived as paradigmatic local quantum information carriers. Despite superior controllability and configurability, their practical performance as qubits through either motional or spin states depends critically on their material environment. In this talk, I will present our experimental realization of a new qubit platform based on isolated single electrons trapped on an ultraclean solid neon surface in vacuum. By integrating an electron trap in a circuit quantum electrodynamics architecture, we achieve strong coupling between the motional states of a single electron and a single microwave photon in an on-chip superconducting resonator [1]. Qubit gate operations and dispersive readout are successfully implemented. Our latest measurements show that both the relaxation time T1 and coherence time T2 have reached 0.100-millisecond scale [2]. The observed single-shot readout fidelity, without using a quantum-limited amplifier, is already 98.1%. The average single-qubit fidelity using Clifford-based randomized benchmarking is 99.97%. Simultaneous strong coupling of two qubits with the microwave resonator is also demonstrated, as a first step toward two-qubit entangling gates for universal quantum computing. These results manifest that the electron-on-solid-neon (eNe) charge qubits have outperformed all the existing charge qubits to date and rivaled the state-of-the-art superconducting transmon qubits.
[1] X. Zhou … and D. Jin, “Single electrons on solid neon as a solid-state qubit platform”, Nature 605, 46–50 (2022).
[2] X. Zhou … and D. Jin, “Electron charge qubits on solid neon with 0.1 millisecond coherence time”, manuscript submitted (2022).