IRRADIATION-INDUCED DISORDER IN HIGH-T-C CUPRATES - ELECTRONIC BAND-STRUCTURE STUDY

We used thermal neutron irradiation to produce disorder in Bi-2212 sin gle crystals (T-c = 85 K), at a constant carrier density. The irradiat ed samples were insulators. High-temperature superconductivity with a lower T-c than prior to irradiation could be restored by a low-tempera ture annealing. We performed angle-resolved photoemission investigatio n on both unannealed (insulating) and annealed (superconducting) sampl es in order to study the corresponding changes in electronic structure . We observed a strong suppression of the spectral weight near the Fer mi energy with increasing disorder. Our results demonstrate that effec ts related to disorder cannot be neglected in the interpretation of th e spectral properties of cuprates. (C) 1998 Elsevier Science B.V. All rights reserved.