  Magnetic nanoparticles (MNP's) have become increasingly important in heating
applications such as hyperthermia treatment of cancer due to their ability to
release heat when a remote external alternating magnetic field is applied. It
has been shown that the heating capability of such particles varies
significantly with the size of particles used. In this paper, we theoretically
evaluate the heating capability of rod-shaped MNP's and identify conditions
under which these particles display highest efficiency. For optimally sized
monodisperse particles, the power generated by rod-shaped particles is found to
be equal to that generated by spherical particles. However, for particles which
have a dispersion in size, rod-shaped particles are found to be more effective
in heating as a result of the greater spread in the power density distribution
curve. Additionally, for rod-shaped particles, a dispersion in the radius of
the particle contributes more to the reduction in loss power when compared to a
dispersion in the length. We further identify the optimum size, i.e the radius
and length of nanorods, given a bi-variate log-normal distribution of particle
size in two dimensions.
