<title>Electronic Raman scattering in copper-oxide superconductors and related compounds</title>

Abstract

We describe Raman-scattering experiments in copper-oxide superconductors with transition temperatures between 12 and 90 K as a function of temperature and polarization. The broad continuum observed in all compounds in both the normal and the superconducting state is attributed predominantly to electronic excitations and will be interpreted in terms of charge- carrier fluctuations. The effect of impurities is studied systematically. The limitations of the present theoretical approach as well as possible generalizations are discussed.