Electronic Structure of Sr$_{2}$RhO$_{4}$ investigated by ARPES

We investigated the electronic structure of 4d-transition metal oxides Sr$_{2}$RhO$_{4 }$by high-resolution ARPES(angle-resolved photoemission spectroscopy) and compared the results with density-functional electronic structure calculation. Sr$_{2}$RhO$_{4 }$has the same crystal structure with Sr$_{2}$RuO$_{4 }$and just one more electron than Sr$_{2}$RuO$_{4}$ in 4d orbitals. But ARPES data reveal very different Fermi surface from that expected in the simple rigid-band picture, and especially the electronic structure related to the d$_{xy}$ band-the full occupation and missing at Fermi surface of the d$_{xy}$ band- is qualitatively different from Sr$_{2}$RuO$_{4}$. This turns out to be due to the fact that RhO$_{6}$ octahedra are rotated about the c-axis. We will discuss how the rotation of octahedra change the electronic structure by comparing the ARPES experimental results with density-functional electronic structure calculation in real crystal structure of Sr$_{2}$RhO$_{4}$.