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Self-organization of charge under pressure in the organic conductor (TMTSF)2ReO4

C. Colin·P. Auban-Senzier·C. R. Pasquier·K. Bechgaard
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Abstract

(TMTSF)2ReO4 presents a phase coexistence between two anion orderings defined by their wave vectors q_2=(1/2,1/2,1/2) and q_3=(0,1/2,1/2) in a wide range of pressure (8-11kbar) and temperature. From the determination of the anisotropy of the conductivity and the superconducting transitions in this regime we were able to extract the texture which results from a self-organization of the orientations of the ReO4 anions in the sample. At the lowest pressures, the metallic parts, related to the q_3 order, form droplets elongated along the a-axis embedded in the semiconducting matrix associated with the q_2 order. Above 10kbar, filaments along the a-axis extend from one end of the sample to the other nearly up to the end of the coexistence regime. A mapping of the system into an anisotropic Ising lattice is satisfactory to analyze the data. satisfactory to analyze the data.

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C. Colin, P. Auban-Senzier, C. R. Pasquier, K. Bechgaard. 2006-04-04. Self-organization of charge under pressure in the organic conductor (TMTSF)2ReO4. https://doi.org/10.1209/epl%2Fi2006-10096-6

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