Speaker
Description
Levitating electrons on solid neon form an emerging qubit platform in which the active electron is confined primarily in vacuum above an ultraclean, weakly polarizable, and predominantly nuclear-spin-free dielectric, enabling strong microwave control with reduced material noise. But electrons loaded from an emitter may localize in unintended potential minima generated by electrode gaps, etched trenches, or nanoscale neon morphology. Here we present a geometry-engineering strategy for reproducible single-electron confinement on solid neon using a planar dielectric interlayer combined with a selectively etched trapping trench.
We develop a three-dimensional finite-difference Schrodinger--Poisson framework to compute the electrostatic potential, bound states, orbital splittings, and wavefunction localization of levitating electrons above realistic device stacks. The model is first benchmarked against a smooth gate-defined solid-neon trap, yielding an orbital splitting of $\Delta E/h = 6.212$ GHz, within 3.3% of experimentally reported values. We then show that surface bumps and valleys create parasitic bound states with distinct orbital symmetries and also random correlated roughness, which shifts the qubit frequency considerably, demonstrating strong spectral sensitivity to uncontrolled topography. To suppress this disorder, we demonstrate that a dielectric spacer can planarize the neon template and reduce roughness-induced trapping. Selective dielectric etching then locally restores gate-field penetration at the desired qubit location. These results establish a solid framework that can model levitating-electron qubits and also provide direction towards dielectric surface engineering as a scalable route toward deterministic electron trapping.
| I am the presenting author | Yes |
|---|