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Correlation induced phonon softening in low density coupled bilayer systems

E. H. Hwang·S. Das Sarma
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Abstract

We predict a possible phonon softening instability in strongly correlated coupled semiconductor bilayer systems. By studying the plasmon-phonon coupling in coupled bilayer structures, we find that the renormalized acoustic phonon frequency may be softened at a finite wave vector due to many-body local field corrections, particularly in low density systems where correlation effects are strong. We discuss experimental possibilities to search for this predicted phonon softening phenomenon.

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E. H. Hwang, S. Das Sarma. 2000-12-27. Correlation induced phonon softening in low density coupled bilayer systems. https://doi.org/10.1103/physrevb.63.233201

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