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تسجيل مستخدم جديدNonlinear Conduction by Melting of Stripe-Type Charge Order in Organic Conductors with Triangular Lattices
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We theoretically discuss the mechanism for the peculiar nonlinear conduction in quasi-two-dimensional organic conductors theta-(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 Greens 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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