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arXiv · 1005.0926

Crossover region between nodal and anti-nodal states at the Fermi level of optimally and overdoped Bi$_{2}$Sr$_{1.6}$Nd$_{0.4}$CuO$_{6+\delta}$

D. R. Garcia·J. Graf·C. Jozwiak·C. G. Hwang·H. Eisaki·A. Lanzara
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Abstract

We have studied Bi$_{2}$Sr$_{1.6}$Nd$_{0.4}$CuO$_{6+\delta}$ using Angle Resolved Photoemission Spectroscopy in the optimal and overdoped regions of the phase diagram. We identify a narrow crossover region in the electronic structure between the nodal and antinodal regions associated with the deviation from a pure d-wave gap function, an abrupt increase of the quasiparticle lifetime, the formation of Fermi arcs above T$_c$, and a sudden shift of the bosonic mode energy from higher energy, $\sim${60meV}, near the nodal direction, to lower energy, $\sim${20meV}, near the antinodal direction. Our work underscores the importance of a unique crossover region in the momentum space near E$_F$ for the single layered cuprates, between the nodal and antinodal points, that is independent of the antiferromagnetic zone boundary.

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D. R. Garcia, J. Graf, C. Jozwiak, C. G. Hwang, H. Eisaki, A. Lanzara. 2010-05-06. Crossover region between nodal and anti-nodal states at the Fermi level of optimally and overdoped Bi$_{2}$Sr$_{1.6}$Nd$_{0.4}$CuO$_{6+\delta}$. https://doi.org/10.1103/physrevb.81.184527

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