Highly resolved photoemission on High-T-c's of the BiSrCaCuO-family

The critical temperature T-c attainable with BiSrCaCuO high-temperature sup erconductors depends on the number of CuO2 layers per unit cell (n = 1-4). Here se give an overview of our results achieved so far on single crystalli ne material with n = 1 (T-c = 29 K at optimal doping) and n = 3 (T-c = 108 K) such layers in comparison to the extensively studied n = 3 compound (T-c = 89 K). The investigations involve highly resolved photoemission spectra along major symmetry lines and polarization studies. The polarization studi es were performed at a crossed undulator synchrotron beamline enabling an i n situ variation of light polarization without moving the sample. (C) 1999 Elsevier Science B.V. All rights reserved.