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Observation of an unconventional metal-insulator transition in overdoped CuO_2 compounds

F. Venturini·M. Opel·T. P. Devereaux·J. K. Freericks·I. Tüttő·B. Revaz·E. Walker·H. Berger·L. Forró·R. Hackl
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Abstract

The electron dynamics in the normal state of Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ is studied by inelastic light scattering over a wide range of doping. A strong anisotropy of the electron relaxation is found which cannot be explained by single-particle properties alone. The results strongly indicate the presence of an unconventional quantum-critical metal-insulator transition where "hot" (antinodal) quasiparticles become insulating while "cold" (nodal) quasiparticles remain metallic. A phenomenology is developed which allows a quantitative understanding of the Raman results and provides a scenario which links single- and many-particle properties.

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F. Venturini, M. Opel, T. P. Devereaux, J. K. Freericks, I. Tüttő, B. Revaz, E. Walker, H. Berger, L. Forró, R. Hackl. 2002-06-12. Observation of an unconventional metal-insulator transition in overdoped CuO_2 compounds. https://doi.org/10.1103/physrevlett.89.107003

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