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Formation of two-dimensional weak localization in conducting Langmuir-Blodgett films

Yasuo Ishizaki·Mitsuru Izumi·Hitoshi Ohnuki·Krystyna Kalita-Lipinska·Tatsuro Imakubo·Keiji Kobayashi
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Abstract

We report the magnetotransport properties up to 7 T in the organic highly conducting Langmuir-Blodgett(LB) films formed by a molecular association of the electroactive donor molecule bis(ethylendioxy)tetrathiafulvalene (BEDO-TTF) and stearic acid CH$_3$(CH$_2$)$_{16}$COOH. We show the logarithmic decrease of dc conductivity and the negative transverse magnetoresistance at low temperature. They are interpreted in the weak localization of two-dimensional (2D) electronic system based on the homogeneous conducting layer with the molecular size thickness of BEDO-TTF. The electronic length with phase memory is given at the mesoscopic scale, which provides for the first time evidence of the 2D coherent charge transport in the conducting LB films.

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Yasuo Ishizaki, Mitsuru Izumi, Hitoshi Ohnuki, Krystyna Kalita-Lipinska, Tatsuro Imakubo, Keiji Kobayashi. 2000-10-28. Formation of two-dimensional weak localization in conducting Langmuir-Blodgett films. https://doi.org/10.1103/physrevb.63.134201

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