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arXiv · 0906.0269

Insulator-metal transition in biased finite polyyne systems

A. La Magna·I. Deretzis·V. Privitera
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Abstract

A method for the study of the electronic transport in strongly coupled electron-phonon systems is formalized and applied to a model of polyyne chains biased through metallic Au leads. We derive a stationary non equilibrium polaronic theory in the general framework of a variational formulation. The numerical procedure we propose can be readily applied if the electron-phonon interaction in the device hamiltonian can be approximated as an effective single particle electron hamiltonian. Using this approach, we predict that finite polyyne chains should manifest an insulator-metal transition driven by the non-equilibrium charging which inhibits the Peierls instability characterizing the equilibrium state.

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A. La Magna, I. Deretzis, V. Privitera. 2009-06-01. Insulator-metal transition in biased finite polyyne systems. https://doi.org/10.1140/epjb/e2009-00220-6

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