Bulk electronic structure of superconducting LaRu2P2 single crystals measured by soft-X-ray angle-resolved photoemission spectroscopy

Phys Rev Lett. 2012 Jun 22;108(25):257005. doi: 10.1103/PhysRevLett.108.257005. Epub 2012 Jun 19.

Abstract

We present a soft x-ray angle-resolved photoemission spectroscopy (SX-ARPES) study of the stoichiometric pnictide superconductor LaRu(2)P(2). 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 (~2-3) is negligible in LaRu(2)P(2) even though the mass enhancement is similar in both systems. Our results suggest that the superconductivity in LaRu(2) P(2) 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.