Spectroscopy evidences for true Landau Fermi quasiparticles in LSCO

Claudia Giuseppina Fatuzzo
2014
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Résumé

Improving our knowledge of the normal state of high-temperature cuprate superconductors is believed to represent an important, and maybe necessary, step to advance in our understanding of their unconventional superconducting state. In this talk we present an angle resolved photoemission spectroscopy of an overdoped cuprate system (La1.77Sr0.23CuO4) [1,2]. We will show how the nodal low-energy excitations are consistent with true Landau Fermi quasiparticles [1]. Furthermore, we will show how the quasiparticle description of the excitations breaks down both for high energies and in spectra recorded in the anti-nodal region [2]. [1] C. G. Fatuzzo et al., submitted. [2] J. Chang et al., Nature Communications, 4, 2559 (2013)

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