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arXiv · 1306.3731

Sharp low energy feature in single-particle spectra due to forward scattering in $d$-wave cuprate superconductors

Seung Hwan Hong·Jin Mo Bok·Wentao Zhang·Junfeng He·X. J. Zhou·Chandra M. Varma·Han-Yong Choi
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Abstract

There is an enormous interest in renormalization of quasi-particle (qp) dispersion relation of cuprate superconductors both below and above the critical temperature $T_c$ because it enables determination of the fluctuation spectrum to which the qps are coupled. A remarkable discovery by angle-resolved photoemission spectroscopy (ARPES) is a sharp low energy feature (LEF) in qp spectra well below the superconducting energy gap but with its energy increasing in proportion to $T_c$ and its intensity increasing sharply below $T_c$. This unexpected feature needs to be reconciled with $d$-wave superconductivity. Here, we present a quantitative analysis of ARPES data from Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ (Bi2212) using Eliashberg equations to show that the qp scattering rate due to the forward scattering impurities far from the Cu-O planes is modified by the energy gap below $T_c$ and shows up as the LEF. This is also a necessary step to analyze ARPES data to reveal the spectrum of fluctuations promoting superconductivity.

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Seung Hwan Hong, Jin Mo Bok, Wentao Zhang, Junfeng He, X. J. Zhou, Chandra M. Varma, Han-Yong Choi. 2014-06-30. Sharp low energy feature in single-particle spectra due to forward scattering in $d$-wave cuprate superconductors. https://doi.org/10.1103/physrevlett.113.057001

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