arXiv 0812.37322008-12cond-mat.str-elcond-mat.supr-con

Bandwidth tuning triggers interplay of charge order and superconductivity in two-dimensional organic materials

S. Kaiser, M. Dressel, Y. Sun, A. Greco, J. A. Schlueter, G. L. Gard, N. Drichko

备注：: 5 pages, 4 figures
发表信息：: Phys. Rev. Lett. 105, 206402 (2010)
DOI：: 10.1103/PhysRevLett.105.206402

英文摘要：

We observe charge-order fluctuations in the quasi-two-dimensional organic superconductor $β^{\prime\prime}$-(BEDT-TTF)2 SF5 CH2 CF2 SO3 both by means of vibrational spectroscopy, locally probing the fluctuating charge order, and investigating the in-plane dynamical response by infrared reflectance spectroscopy. The decrease of effective electronic interaction in an isostructural metal suppresses both charge-order fluctuations and superconductivity, pointing on their interplay. We compare the results of our experiments with calculations on the extended Hubbard model.

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