A multicore magnetic particle. In one embodiment, the magnetic particle includes a plurality of superparmagnetic cores embedded in a non-magnetic matrix. In another embodiment, the effective anisotropy energy barrier of the particle is larger than the sum of the anisotropy energy barriers of the individual superparamagnetic cores. In yet another embodiment, the superparamagnetic cores are close enough to interact magnetically by exchange coupling and dipole interaction. In still yet another embodiment, the specific loss power of the magnetic particle is greater than the specific loss power of an equivalent mass of individual superparamagnetic cores.
