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arXiv · 1310.6856

Charge order and possible bias-induced metastable state in the organic conductor β-(meso-DMBEDT-TTF)2PF6: effects of structural distortion

Yasuhiro Tanaka·Kenji Yonemitsu
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Abstract

We theoretically investigate charge order and nonlinear conduction in a quasi-two-dimensional organic conductor β-(meso-DMBEDT-TTF)2PF6 [DMBEDT-TTF=dimethylbis(ethylenedithio)tetrathiafulvalene]. Within the Hartree-Fock approximation, we study effects of structural distortion on the experimentally observed checkerboard charge order and its bias-induced melting by using an extended Hubbard model with Peierls- and Holstein-types of electron-lattice interactions. The structural distortion is important in realizing the charge order. The current-voltage characteristics obtained by a nonequilibrium Green's function method indicate that a charge-ordered insulating state changes into a conductive state. Although the charge order and lattice distortions are largely suppressed at a threshold voltage, they remain finite even in the conductive state. We discuss the relevance of the results to experimental observations, especially to a possible bias-induced metastable state.

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Yasuhiro Tanaka, Kenji Yonemitsu. 2013-10-25. Charge order and possible bias-induced metastable state in the organic conductor β-(meso-DMBEDT-TTF)2PF6: effects of structural distortion. https://doi.org/10.1088/0953-8984%2F25%2F46%2F465603

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