Physics Graduate Student Seminar with Kaiwen Zheng on Effect of cryogenic film growth on floating electrons trapped on neon surface

Free electrons can spontaneously float above the surface of a neon thin film due to its negative electron affinity and weak polarization force. Recent works have shown that the quantized motional states of these electrons can be coherently controlled and read out by microwave pulses delivered through on-chip superconducting circuits. The behavior of these electrons is strongly dependent on the surface morphology and growth conditions of the neon film, and a deeper understanding of it is needed to scale up this qubit platform. In this talk, I will walk through our experience of observing many electrons trapped on neon surfaces grown at different conditions in the past year and attempt to build an intuitive picture of what’s happening.