ARPES photointensity computations on Bi2201 high Tc superconductor:
Origin of the shadow band

Matti Lindroos

Physics Department, Tampere University of Technology, Tampere, Finland and
Physics Department, Northeastern University, Boston, Massachusetts, USA

We have carried out model ARPES computations on Bi2201 within the first principles band theory framework. Here we focus on understanding the nature of the so-called "shadow" band which has been observed in ARPES experiments on Bi-compounds. An attempt is made to delineate ARPES signatures associated with orthorhombic distortion of the tetragonal lattice as well as those arising from modulation of the charge or the spin density in the system. In this way, we hope to gain a handle on the mechanism responsible for the origin of the shadow band in terms of its photointensity characteristics. We discuss implications of these results and the extent to which the ARPES intensity of the shadow band can be viewed as a simple replica of the pristine underlying band structure. ** Work done in collaboration with V. Arpiainen, A. Bansil, Hsin Lin, R. S. Markiewicz and S. Sahrakorpi.