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Updated: Jun 22, 2026
Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
Far-infrared absorption and the metal-to-insulator transition in hole-doped cuprates
1CNR-INFM Coherentia and Dipartimento di Fisica, Università di Roma La Sapienza, I-00185 Roma, Italy.
Abstract:
By studying the optical conductivity of Bi(2)Sr(2-x)La(x)CuO(6) and Y(0.97)Ca(0.03)Ba(2)Cu(3)O(6), we show that the metal-to-insulator transition 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 midinfrared softens with doping but is less sensitive to the metal-to-insulator transition.
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