Magnetic detonation structure in crystals of nanomagnets controlled by thermal conduction and volume viscosity

Experimentally detected ultrafast spin avalanches spreading in crystals of molecular (nano) magnets [Decelle et al., Phys. Rev. Lett. 102, 027203 (2009)] have recently been explained in terms of magnetic detonation [Modestov et al., Phys. Rev. Lett. 107, 207208 (2011)]. Here magnetic detonation structure is investigated by taking into account transport processes of the crystals such as thermal conduction and volume viscosity. The transport processes result in smooth profiles of the most important thermodynamical crystal parameters, temperature, density, and pressure, all over the magnetic detonation front, including the leading shock, which is one of the key regions of magnetic detonation. In the case of zero volume viscosity, thermal conduction leads to an isothermal discontinuity instead of the shock, for which temperature is continuous while density and pressure experience jump. It is also demonstrated that the thickness of the magnetic detonation front may be controlled by applying the transverse-magnetic field, which is important for possible experimental observations of magnetic detonation.