Signature of the CuO2 plane related bands in YBa 2Cu3O(6.9) as seen by angle-resolved photoemission

摘要

The authors present first-principles computations together with corresponding angle-resolved photoemission measurements in order to delineate the shape and polarization dependence of the spectral feature associated with the CuO(sub 2) plane-related bands from the (001) surface of YBa(sub 2)Cu(sub 3)O(sub 6.9). Theoretical predictions are found to be in remarkable agreement with the observed character of the spectral feature between 0 and 0.3 eV binding energy (for k(sub (parallel)) values along the (Gamma)-S line), and indicate that the local-density-approximation based wave-functions implicit in the theory provide a reasonable description of the CuO(sub 2) plane band states near the Fermi energy. The computations also show that of the six possible surface terminations, the ARPES spectra from Y123(001) surface are reasonably described by the BaO/CuO(sub 2) ideal surface termination, i.e. by assuming a BaO layer followed by a CuO(sub 2) plane layer below.