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Dynamical Kohn Anomaly in Surface Acoustic Wave Response in Quantum Hall Systems Near $ν= 1/2$

Nataliya A. Zimbovskaya·Joseph L. Birman
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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 $Delta s/s$ and attenuation coefficient $Γ$. The effect is considerably enhanced under periodic modulation and should be observable.

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Nataliya A. Zimbovskaya, Joseph L. Birman. 2005-07-13. Dynamical Kohn Anomaly in Surface Acoustic Wave Response in Quantum Hall Systems Near $ν= 1/2$. https://doi.org/10.1103/physrevb.60.2864

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