title: Propagation of magnetic avalanches in Mn12Ac at high field sweep rates.
abstract: Time-resolved measurements of the magnetization reversal in single crystals of Mn12Ac in pulsed magnetic fields, at magnetic field sweep rates from 1.5 kT/s up to 7 kT/s, suggest a new process that cannot be scaled onto a deflagrationlike propagation driven by heat diffusion. The sweep rate dependence of the propagation velocity, increasing from a few 100 m/s up to the speed of sound in Mn12Ac, indicates the existence of two new regimes at the highest sweep rates, with a transition around 4 kT/s that can be understood as a magnetic deflagration-to-detonation transition.
authors.affiliation: INPAC-Institute for Nanoscale Physics and Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium.
authors.forename: W
authors.initials: W
authors.lastname: Decelle
authors.forename: J
authors.initials: J
authors.lastname: Vanacken
authors.forename: V V
authors.initials: VV
authors.lastname: Moshchalkov
authors.forename: J
authors.initials: J
authors.lastname: Tejada
authors.forename: J M
authors.initials: JM
authors.lastname: Hernández
authors.forename: F
authors.initials: F
authors.lastname: Macià