Abstract
We present a soft x-ray angle-resolved photoemission spectroscopy (SX-ARPES) study of the stoichiometric pnictide superconductor . The observed electronic structure is in good agreement with density functional theory (DFT) calculations. However, it is significantly different from its counterpart in high-temperature superconducting Fe pnictides. In particular, the bandwidth renormalization present in the Fe pnictides () is negligible in even though the mass enhancement is similar in both systems. Our results suggest that the superconductivity in has a different origin with respect to the iron pnictides. Finally, we demonstrate that the increased probing depth of SX-ARPES, compared to the widely used ultraviolet ARPES, is essential in determining the bulk electronic structure in the experiment.
- Received 26 January 2012
DOI:https://doi.org/10.1103/PhysRevLett.108.257005
© 2012 American Physical Society