Observation of an unconventional metal-insulator transition in overdoped CuO2 compounds
F Venturini1, M Opel, T P Devereaux
1Walther Meissner Institute, Bavarian Academy of Sciences, 85748 Garching, Germany.
Abstract:
The electron dynamics in the normal state of Bi(2)Sr(2)CaCu(2)O(8+delta) 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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