Controlling toroidal moments by crossed electric and magnetic fields

The control of ferroelastic, ferroelectric, and ferromagnetic domains through the corresponding fields has led to numerous applications taken for granted nowadays. Ferrotoroidal order on the other hand has been less explored due to its more complex character and due to the peculiar field needed to control it. LiFeSi${}_{2}$O${}_{6}$ exhibits a ferrotoroidal order that is particularly simple to analyze. By performing neutron-diffraction experiments with spherical polarization analysis we show that crossed electric and magnetic fields allow us to control ferrotoroidal moments.