Dynamical Kohn Anomaly in Surface Acoustic Wave Response in Quantum Hall Systems Near ν=1/2
Abstract
The dynamical analog of the Kohn Anomaly image of the Fermi Surface is demonstrated for the response functions to the surface acoustic waves in Quantum Hall Systems near
ν=1/2
. Kinks appear in the velocity shift
Deltas/s
and attenuation coefficient
Γ
. The effect is considerably enhanced under periodic modulation and should be observable.