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Electric-Field-Induced Mott Insulating States in Organic Field-Effect Transistors

Olivier Cepas·Ross H. McKenzie
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Abstract

We consider the possibility that the electrons injected into organic field-effect transistors are strongly correlated. A single layer of acenes can be modelled by a Hubbard Hamiltonian similar to that used for the kappa-(BEDT-TTF)(2)X family of organic superconductors. The injected electrons do not necessarily undergo a transition to a Mott insulator state as they would in bulk crystals when the system is half-filled. We calculate the fillings needed for obtaining insulating states in the framework of the slave-boson theory and in the limit of large Hubbard repulsion, U. We also suggest that these Mott states are unstable above some critical interlayer coupling or long-range Coulomb interaction.

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Olivier Cepas, Ross H. McKenzie. 2002-10-25. Electric-Field-Induced Mott Insulating States in Organic Field-Effect Transistors. https://doi.org/10.1103/physrevb.66.214528

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