Abstract

Electrons floating on condensed noble-gas substrates form a remarkably clean material system that is minimally influenced by the underlying host material, and recent experiments have explored their potential as a qubit platform. In particular, single electrons floating on solid neon thin films have attracted significant interest because they exhibit long coherence times when probed with superconducting circuits at frequencies around 6 GHz. Surprisingly, however, the energy spectrum of these qubits resembles that of a two-level-system defect more than the spectrum expected from the Coulomb potential defined by the bias electrodes. In this thesis, I first review floating-electron systems and the experimental methods used to probe their quantum states. I then show that electron-on-neon qubits with transition frequencies of a few GHz are observed only on neon films deposited on silicon surfaces, and not on neon films deposited on sapphire. Motivated by this observation, I propose a model in which a floating electron on the neon surface interacts with fixed positive charge defects in the native oxide at the silicon surface. Using realistic parameters, this model reproduces the observed voltage-dependent transition frequency and coupling strength of electron-on-neon qubits.

Committee Chair

Kater Murch

Committee Members

Dafei Jin; Erik Henriksen; Li Yang; Sheng Ran

Degree

Doctor of Philosophy (PhD)

Author's Department

Physics

Author's School

Graduate School of Arts and Sciences

Document Type

Dissertation

Date of Award

7-28-2026

Language

English (en)

Download

Available for download on Thursday, July 27, 2028

Included in

Physics Commons

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