Engineering of micron-sized electron trap in a superconducting tuning-fork resonator

Electrons on helium is a unique two-dimensional electron gas system formed at the interface of a quantum liquid (superfluid helium) and vacuum. The motional and spin states of single-electron quantum dots defined on such systems have been proposed for hybrid quantum computing [1,2]. Here, we will present experiments in which an ensemble of electrons are trapped above a tuning fork superconducting resonator and describe their coupling with both the differential and common mode. Next, we will discuss the design of superconducting resonators with a micron-sized trapping area and a reduced number of trapped electrons, and the experimental progress towards a single trapped electron regime.\\[4pt] [1] S. Lyon, Phys. Rev. A. 74, 5 (2006)\\[0pt] [2] D.I. Schuster, et al. Phys. Rev. Lett. 105, 040503 (2010)