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Equilibrium magnetic properties and Meissner expulsion of magnetic flux in General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Received 7 January 1994 AbstractThe unusual spatial transformation of the magnetic-flux structure in Bi2Sr2CaCu2Ox single crystals during magnetization of zero-field cooled samples and during field cooling (the Meissner flux expulsion) is directly visualized by means of the magnetooptical technique. In both cases similar inhomogeneous flux distributions are observed at high temperatures in a magnetic field applied perpendicularly to the basal plane: The magnetic field in the crystal center is approximately equal to the applied field, but at the crystal perimeter a belt of lower field occurs. A model of such an equilibrium flux structure is developed taking into account the real shape of the crystals. The distribution of the Meissner screening current in this geometry is directly measured for the first time.