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arXiv · 1804.02453

Unambiguous connection between the Fermi surface topology and the pseudogap in Bi$_{2}$Sr$_2$CaCu$_2$O$_{8+d}$

B. Loret·Y. Gallais·M. Cazayous·R. D. Zhong·J. Schneeloch·G. D. Gu·A. Fedorov·T. K. Kim·S. V. Borisenko·A. Sacuto
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Abstract

We study the behavior of the pseudogap in overdoped Bi$_{2}$Sr$_2$CaCu$_2$O$_{8+d}$ by electronic Raman scattering (ERS) and angle-resolved photoemission spectroscopy (ARPES) on the same single crystals. Using both techniques we find that, unlike the superconducting gap, the pseudogap related to the anti-bonding band vanishes above the critical doping p$_c$ = 0.22. Concomitantly, we show from ARPES measurements that the Fermi surface of the anti-bonding band is hole-like below pc and becomes electron-like above p$_c$. This reveals that the appearance of the pseudogap depends on the Fermi surface topology in Bi$_{2}$Sr$_2$CaCu$_2$O$_{8+d}$ , and more generally, puts strong constraint on theories of the pseudogap phase.

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B. Loret, Y. Gallais, M. Cazayous, R. D. Zhong, J. Schneeloch, G. D. Gu, A. Fedorov, T. K. Kim, S. V. Borisenko, A. Sacuto. 2018-04-06. Unambiguous connection between the Fermi surface topology and the pseudogap in Bi$_{2}$Sr$_2$CaCu$_2$O$_{8+d}$. https://doi.org/10.1103/physrevb.97.174521

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