  We report that the fundamental three-dimensional (3-D) scattering
single-channel limit can be overcome in magneto-optical assisted systems by
inducing nondegenerate magnetoplasmonic modes. In addition, we propose a 3-D
active (magnetically assisted) forward-superscattering to invisibility switch,
functioning at the same operational wavelength. Our structure is composed of a
high-index dielectric core coated by indium antimonide (InSb), a semiconductor
whose permittivity tensorial elements may be actively manipulated by an
external magnetic bias $B_0$. In the absence of $B_0$, InSb exhibits isotropic
epsilon-near-zero (ENZ) and plasmonic behavior above and below its plasma
frequency, respectively, a frequency band which can be utilized for attaining
invisibility using cloaks with permittivity less than that of free space. With
realistic $B_0$ magnitudes as high as 0.17 T, the gyroelectric properties of
InSb enable the lift of mode degeneracy, and the induction of a Zeeman-split
type dipolar magnetoplasmonic mode that beats the fundamental single-channel
limit. This all-in-one design allows for the implementation of functional and
highly tunable optical devices.
