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Large dielectric constant and giant nonlinear conduction in the organic conductor theta-(BEDT-TTF)_2CsZn(SCN)_4

K. Inagaki·I. Terasaki·H. Mori·T. Mori
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Abstract

The dielectric constant and ac conductivity have been measured for the layered organic conductor theta-(BEDT-TTF)_2CsZn(SCN)_4 along the out-of-plane direction, which show a relaxation behavior similar to those in the charge-density-wave conductor. Most unexpectedly, they exhibit a large bias dependence with a hysteresis, and changes in magnitude by 100-1000 times at a threshold. These findings are very similar to the collective excitation of the charge density wave. theta-$(BEDT-TTF)_2CsZn(SCN)_4 has collective excitations associated with charge ordering, though it shows no clear indication of long range order.

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K. Inagaki, I. Terasaki, H. Mori, T. Mori. 2004-09-09. Large dielectric constant and giant nonlinear conduction in the organic conductor theta-(BEDT-TTF)_2CsZn(SCN)_4. https://doi.org/10.1143/jpsj.73.3364

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