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arXiv · 0905.0568

Far-infrared absorption and the metal-to-insulator transition in hole-doped cuprates

S. Lupi·D. Nicoletti·O. Limaj·L. Baldassarre·M. Ortolani·P. Calvani·S. Ono·Yoichi Ando
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Abstract

By studying the optical conductivity of BSLCO and YCBCO, we show that the metal-to-insulator transition (MIT) in these hole-doped cuprates is driven by the opening of a small gap at low T in the far infrared. Its width is consistent with the observations of Angle-Resolved Photoemission Spectroscopy in other cuprates, along the nodal line of the k-space. The gap forms as the Drude term turns into a far-infrared absorption, whose peak frequency can be approximately predicted on the basis of a Mott-like transition. Another band in the mid infrared softens with doping but is less sensitive to the MIT.

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S. Lupi, D. Nicoletti, O. Limaj, L. Baldassarre, M. Ortolani, P. Calvani, S. Ono, Yoichi Ando. 2009-05-05. Far-infrared absorption and the metal-to-insulator transition in hole-doped cuprates. https://arxiv.org/abs/0905.0568

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