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ARPES Study of the Metal-Insulator Transition in Bismuth Cobaltates

Z. Yusof·B. O. Wells·T. Valla·P. D. Johnson·A. V. Fedorov·Q. Li·S. M. Loureiro·R. J. Cava
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Abstract

We present an angle-resolved photoemission spectroscopy (ARPES) study of a Mott-Hubbard-type bismuth cobaltate system across a metal-insulator transition. By varying the amount of Pb substitution, and by doping with Sr or Ba cation, a range of insulating to metallic properties is obtained. We observe a systematic change in the spectral weight of the coherent and incoherent parts, accompanied by an energy shift of the incoherent part. The band dispersion also shows the emergence of a weakly dispersing state at the Fermi energy with increasing conductivity. These changes correspond with the changes in the temperature-dependent resistivity behavior. We address the nature of the coherent-incoherent parts in relation to the peak-dip-hump feature seen in cuprates superconductors.

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Z. Yusof, B. O. Wells, T. Valla, P. D. Johnson, A. V. Fedorov, Q. Li, S. M. Loureiro, R. J. Cava. 2006-10-10. ARPES Study of the Metal-Insulator Transition in Bismuth Cobaltates. https://doi.org/10.1103/physrevb.76.165115

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