AC and DC magnetization of finite cylindrical and orthorhombic superconductors

It is well known that demagnetizing effects arising in samples of finite le ngth may drastically modify the magnetic response of superconductors. In th is work we report the study of how demagnetizing effects influence the resp onse of finite superconductors of cylindrical and orthorhombic shape in the Meissner state. We have measured both the ac susceptibility and de magneti zation of a set of niobium samples with different dimensions. We compare th e experimental results with calculations from a model based on energy minim ization in the superconductor. A good agreement is observed for a wide rang e of sample sizes.