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Doping dependence of an n-type cuprate superconductor investigated by ARPES

N. P. Armitage·F. Ronning·D. H. Lu·C. Kim·A. Damascelli·K. M. Shen·D. L. Feng·H. Eisaki·Z. -X. Shen·P. K. Mang·N. Kaneko·M. Greven·Y. Onose·Y. Taguchi·Y. Tokura
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Abstract

We present an angle resolved photoemission (ARPES) doping dependence study of the n-type cuprate superconductor Nd_2-xCe_xCuO_4, from the half-filled Mott-insulator to the T_c=24K superconductor. In Nd2CuO4, we reveal the charge-transfer band (CTB) for the first time. As electrons are doped into the system, this feature's intensity decreases with the concomitant formation of near-E_F spectral weight. At low doping, the Fermi surface is an electron-pocket (with volume ~ x) centered at (pi,0). Further doping leads to the creation of a new hole-like Fermi surface (volume ~ 1+x) centered at (pi,pi). These findings shed light on the Mott gap, its doping evolution, as well as the anomalous transport properties of the n-type cuprates.

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N. P. Armitage, F. Ronning, D. H. Lu, C. Kim, A. Damascelli, K. M. Shen, D. L. Feng, H. Eisaki, Z. -X. Shen, P. K. Mang, N. Kaneko, M. Greven, Y. Onose, Y. Taguchi, Y. Tokura. 2002-07-19. Doping dependence of an n-type cuprate superconductor investigated by ARPES. https://doi.org/10.1103/physrevlett.88.257001

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