ARPES study on Ca$_{1.8}$Sr$_{0.2}$RuO$_{4}$

Owing to the discovery of triplet superconductivity in Sr$_{2}$RuO$_{4}$, much effort has been devoted in the past few years to the understanding of the Ca$_{2-x}$Sr$_{x}$RuO$_{4}$ family. These compounds exhibit a rich phase diagram which connects the p-wave superconductor Sr$_{2}$RuO$_{4}$ to the Mott insulator Ca$_{2}$RuO$_{4}$. Particularly, the x = 0.2 compound is at the boundary between a magnetic metal and a canted antiferomagnetic insulator. It has been suggested recently that this compound$_{ }$has d-electron heavy-fermion behavior due to modulations in the magnetic correlations induced by the structural distortion. For such behavior, flat electronic bands are expected. However, our angle resolved photoemission measurements observed only highly dispersive bands.