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Updated: Aug 11, 2026
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Laser based angle-resolved photoemission, the sudden approximation, and quasiparticle-like spectral peaks in
J D Koralek1, J F Douglas, N C Plumb
1Department of Physics, University of Colorado, Boulder, Colorado 80309-0390, USA. Koralek@colorado.edu
Abstract:
A new low photon energy regime of angle-resolved photoemission spectroscopy is accessed with lasers and used to study the high T(C) superconductor Bi2Sr2CaCu2O(8+delta). The low energy increases bulk sensitivity, reduces background, and improves resolution. With this we observe spectral peaks which are sharp on the scale of their binding energy--the clearest evidence yet for quasiparticles in the normal state. Crucial aspects of the data such as the dispersion, superconducting gaps, and the bosonic coupling kink are found to be robust to a possible breakdown of the sudden approximation.
