Coupling Floating Electrons on Liquid Helium to an LC Circuit

ORAL

Abstract

Surface electrons (SEs) on liquid helium offer a clean and well-isolated system for realizing qubits [1]. In this talk, we present detection of the Rydberg state of many SEs by radio frequency reflectometry [2]. Liquid helium is filled halfway between a parallel plate capacitor, which is connected in parallel with a superconducting micro-coil to from an LC circuit with a loaded Q-factor 308 and a resonant frequency 120.94 MHz. After depositing SEs, we excited them to the first Rydberg-state them with microwaves around 165 GHz. When excited, the SEs slightly alter the capacitance of the LC circuit. We apply a probe signal to the LC circuit and measure the reflectance. Furthermore, we discuss the enhancement of the signal arising from the coupling between the Rydberg excitation and the plasmon modes of SEs.



[1] P. M. Platzman, and M. I. Dykman, Science 284, 1967 (1999).

[2] A. Jennings et al., Phys. Rev. Lett. 135, 087001 (2025).

*This work was supported by JST-FOREST (JPMJFR2039) and RIKEN-Hakubi program.

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Presenters

  • ERIKA KAWAKAMI

    • RIKEN

Authors

  • ERIKA KAWAKAMI

    • RIKEN

  • Jun Wang

    • RIKEN Center for Quantum Computing, RIKEN
    • RIKEN

  • Asher Jennings

    • RIKEN Center for Quantum Computing, RIKEN
    • RIKEN

  • Yiran Tian

    • RIKEN Center for Quantum Computing, RIKEN
    • RIKEN

  • Ivan Grytsenko

    • RIKEN

  • Oleksiy Rybalko

    • RIKEN Center for Quantum Computing, RIKEN, and B. Verkin Institute for Low Temperature Physics and Engineering of the NAS of Ukraine
    • RIKEN