Electron Lateral Trapping Induced by Non-Uniform Thickness in Solid Neon Layers

Abstract

Recent experimental advances highlight electron charge qubits floating above solid neon as an emerging promising platform for quantum computing, but the physical origin of single-electron lateral trapping is still not fully understood. While prior theoretical work has mainly examined electrons above bulk solid neon, experimental systems usually feature neon layers of only $\lesssim 10$ nm thickness and non-uniformity, highlighting unresolved questions about how thickness influences electron trapping. Here we theoretically investigate the effect of finite thickness and non-uniformity of solid neon layers on electron trapping. For a 10 nm layer, the electron binding energy is enhanced threefold compared to bulk. Exploiting this thickness dependence, we propose a nanopatterned-substrate mechanism in which engineered thickness variations generate lateral trapping potentials for electrons. The lateral trapping potential can be finely tuned by a perpendicular electric field. Such non-uniform-thickness induced electron charge qubits open a viable pathway toward building multi-qubit systems for quantum computation.