Magneto-optical imaging of magnetic deflagration in Mn12-Acetate

For the first time, the morphology and dynamics of spin avalanches in Mn12-Acetate crystals using magneto-optical imaging has been explored. We observe an inhomogeneous relaxation of the magnetization, the spins reversing first at one edge of the crystal and a few milliseconds later at the other end. Our data fit well with the theory of magnetic deflagration, demonstrating that very slow deflagration rates can be obtained, which makes new types of experiments possible.Comment: 5 two-column pages, 3 figures, EPL styl

Flux creep in Bi2Sr2Ca1Cu2O(8+x) single crystals

Dissipative effects were investigated in Bi2Sr2Ca1Cu2O(8+x) single crystals by critical current and magnetic relaxation measurements. Activation energies for the flux motion were determined from the temperature dependence of the critical current and from the time decay of the zero field cooled and the remanent magnetization. The effective activation energy was found to increase with temperature, in agreement with the existence of a distribution of activation energies (E sub o 20 meV at 4.2 K for H + 10 kOe applied parallel to the c-axis.)

Coreference detection of low quality objects

The problem of record linkage is a widely studied problem that aims to identify coreferent (i.e. duplicate) data in a structured data source. As indicated by Winkler, a solution to the record linkage problem is only possible if the error rate is sufficiently low. In other words, in order to succesfully deduplicate a database, the objects in the database must be of sufficient quality. However, this assumption is not always feasible. In this paper, it is investigated how merging of low quality objects into one high quality object can improve the process of record linkage. This general idea is illustrated in the context of strings comparison, where strings of low quality (i.e. with a high typographical error rate) are merged into a string of high quality by using an n-dimensional Levenshtein distance matrix and compute the optimal alignment between the dirty strings. Results are presented and possible refinements are proposed