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تسجيل مستخدم جديدWaterfalls in cuprates
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New hot topic in ARPES on HTSC, the observation of the so called waterfalls, is addressed. The energy scale at about 0.2-0.3 eV that can be derived from the coherent component of ARPES spectra measured along the nodal direction is not new but has been already discussed in terms of a coupling to a bosonic continuum. However, the waterfalls, namely the long vertical parts of the experimental dispersion around the center of the Brillouin zone (BZ), seem to be purely artificial. They are a consequence of simple matrix-element effect: a complete suppression of the photoemission intensity from both the coherent and incoherent components. When the matrix-elements are taken into account, the latter reveals a grid-like structure along the bonding directions in the BZ.
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