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arXiv · 1108.6115

Nonlinear Conduction by Melting of Stripe-Type Charge Order in Organic Conductors with Triangular Lattices

Yasuhiro Tanaka·Kenji Yonemitsu
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Abstract

We theoretically discuss the mechanism for the peculiar nonlinear conduction in quasi-two-dimensional organic conductors θ-(BEDT-TTF)2X [BEDT-TTF=bis(ethylenedithio)tetrathiafulvalene] through the melting of stripe-type charge order. An extended Peierls-Hubbard model attached to metallic electrodes is investigated by a nonequilibrium Green's function technique. A novel current-voltage characteristic appears in a coexistent state of stripe-type and nonstripe 3-fold charge orders, where the applied bias melts mainly the stripe-type charge order through the reduction of lattice distortion, whereas the 3-fold charge order survives. These contrastive responses of the two different charge orders are consistent with the experimental observations.

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Yasuhiro Tanaka, Kenji Yonemitsu. 2011-08-31. Nonlinear Conduction by Melting of Stripe-Type Charge Order in Organic Conductors with Triangular Lattices. https://doi.org/10.1143/jpsj.80.103702

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