Temperature dependence of the Kondo resonance and its satellites in CeCu2Si2 - art. no. 106401

We present high-resolution photoemission spectroscopy studies on the Kondo resonance of the strongly correlated Ce system CeCu2Si2. By exploiting the thermal broadening of the Fermi edge we analyze position, spectral weight, and temperature dependence of the low-energy 4f spectral features, whose ma jor weight lies above the Fermi level E-F. We also present theoretical pred ictions based on the single-impurity Anderson model using an extended noncr ossing approximation, including all spin-orbit and crystal field splittings of the 4f states. The excellent agreement between theory and experiment pr ovides strong evidence that the spectral properties of CeCu2Si2 can be desc ribed by single-impurity Kondo physics down to T approximate to 5 K.