000002070 001__ 2070 000002070 005__ 20240523045507.0 000002070 0247_ $$2doi$$a10.6082/uchicago.2070 000002070 041__ $$aen 000002070 245__ $$aTrapping a Single Electron on Superfluid Helium Using a Superconducting Resonator 000002070 260__ $$bThe University of Chicago 000002070 269__ $$a2019-12 000002070 300__ $$a147 000002070 336__ $$aDissertation 000002070 502__ $$bPh.D. 000002070 520__ $$aElectrons on helium form a unique two-dimensional system on the interface of superfluid $^4$He and vacuum. At low temperatures and weak confinement, trapped electrons can arrange into strongly correlated states known as Wigner molecules, which can be used to study electron interactions in the absence of disorder, or as a promising resource for quantum computation. Wigner molecules have orbital frequencies in the microwave regime and can therefore be integrated with circuit quantum electrodynamics, which would allow rapid detection and manipulation of such a molecule's orbital state. In this thesis, we demonstrate deterministic preparation of one to four-electron Wigner molecules in an electron-on-helium quantum dot located at the tip of an on-chip microwave resonator. The Wigner molecule dipole coupling to the resonator allows us to measure spectral features of Wigner molecules in the microwave regime. We find that different-sized Wigner molecules have strikingly different spectra, and each spectrum serves as a fingerprint for the molecule's internal structure and its surroundings. By modeling the electron-cavity system, we extract each molecule's orbital frequency and electron configuration. For a single electron, the orbital frequency crosses the cavity resonance and we measure a large coherent electron-photon coupling rate of $g/2\pi = 4.8$ MHz, which exceeds the incoherent cavity decay rate by ten times. These results provide a solid base for the development of an electron-on-helium qubit. Looking forward, our platform allows for new microwave studies of strongly correlated electron states and can be used to couple a single microwave photon to a single electron spin. 000002070 542__ $$fUniversity of Chicago dissertations are covered by copyright. 000002070 650__ $$aCondensed matter physics 000002070 650__ $$aLow temperature physics 000002070 650__ $$aQuantum physics 000002070 653__ $$aCircuit quantum electrodynamics 000002070 653__ $$aElectrons on helium 000002070 653__ $$aLiquid helium 000002070 653__ $$aMicrowave engineering 000002070 653__ $$aStrongly correlated electrons 000002070 653__ $$aWigner molecules 000002070 690__ $$aPhysical Sciences Division 000002070 691__ $$aPhysics 000002070 7001_ $$aKoolstra, Gerwin$$uUniversity of Chicago 000002070 72012 $$aDavid Schuster 000002070 72014 $$aJonathan Simon 000002070 72014 $$aMel Shochet 000002070 72014 $$aShinsei Ryu 000002070 8564_ $$93e098c74-f893-4458-8043-9a78420142d6$$eEmbargo (2020-06-16)$$s40388852$$uhttps://knowledge.uchicago.edu/record/2070/files/Koolstra_uchicago_0330D_15024.pdf 000002070 909CO $$ooai:uchicago.tind.io:2070$$pDissertations$$pGLOBAL_SET 000002070 983__ $$aDissertation