Improvement of the phase transition homogeneity of superheated superconducting tin granules

A considerably improved phase transition homogeneity was observed with superheated superconducting Sn spheres as a result of laser melting and fast cooling. These spheres exhibited a very homogeneous phase transition behaviour independent of the orientation of the spheres with respect to the direction of the external magnetic field. Compared to previously untreated Sn spheres the spread of the phase transition boundaries was reduced by almost an order of magnitude. In addition, we studied mass production of Sn structures using vacuum evaporation and deposition. First encouraging results are reported