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Updated: Aug 14, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Polaronic behavior of undoped high-T(c) cuprate superconductors from angle-resolved photoemission spectra
O Rösch1, O Gunnarsson, X J Zhou
1Max-Planck-Institut für Festkörperforschung, D-70506 Stuttgart, Germany.
Abstract:
We present angle-resolved photoemission spectroscopy (ARPES) data on undoped La2CuO4, indicating polaronic coupling between bosons and charge carriers. Using a shell model, we calculate the electron-phonon coupling and find that it is strong enough to give self-trapped polarons. We develop an efficient method for calculating ARPES spectra in undoped systems. Using the calculated couplings, we find the width of the phonon sideband in good agreement with experiment. We analyze reasons for the observed dependence of the width on the binding energy.
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