Condensed Matter Seminar Series
Ripplonic Lamb Shift for Electrons on Helium Surface
Mark I. Dykman
Michigan State University
Thursday December 1, 11:30 am, Room 298, Physics Building
Electrons on helium surface is an ideal system for studying many-body
phenomena, as it is free from disorder. I will discuss some recently
found phenomena related to the electron coupling to capillary waves on
the helium surface, ripplons, and to the electron-electron interaction.
I will show that two-ripplon processes lead to the Lamb-like shift of
the energy levels of quantized electron motion normal to the surface.
The shift is free from the strong divergence that appears if, following
conventional wisdom, one disregards the 3D character of the electron
motion. It displays a characteristic temperature dependence, which is
in quantitative agreement with the experiment. I will also show that
two-ripplon processes play a smaller role in the electron energy
relaxation than previously assumed. This leads to a long coherence time
of qubits based on quantized lateral states in quantum dots on helium
surface placed into a microwave cavity. I will also discuss a
long-sought effect, the onset of intrinsic resonant bistability of the
response of a quasi-2D electron system to a microwave field, which has
been recently seen in the experiment on electrons on helium and which
is due to the electron correlations.
Host: Stephen Teitsworth