  Magnetic dipolar modes (MDMs) in a quasi 2D ferrite disk are microwave energy
eigenstate oscillations with topologically distinct structures of rotating
fields and unidirectional power flow circulations. At the first glance, this
might seem to violate the law of conservation of an angular momentum, since the
microwave structure with an embedded ferrite sample is mechanically fixed.
However, an angular momentum is seen to be conserved if topological properties
of electromagnetic fields in the entire microwave structure are taken into
account. In this paper we show that due to the topological action of the
azimuthally unidirectional transport of energy in a MDM resonance ferrite
sample there exists the opposite topological reaction on a metal screen placed
near this sample. We call this effect topological Lenz effect. The topological
Lenz law is applied to opposite topological charges, one in a ferrite sample
and another on a metal screen. The MDM originated near fields, the
magnetoelectric (ME) fields, induce helical surface electric currents and
effective charges on a metal. The fields formed by these currents and charges
will oppose their cause.
