  A nano-scale reconfigurable magnonic crystal is designed using
voltage-controlled perpendicular magnetic anisotropy (PMA) in
ferromagnetic-dielectric hetero-structures. A periodic array of gate metallic
stripes is placed on top of a MgO/Co structure in order to apply a periodic
electric field and to modify the PMA in Co. It is numerically demonstrated that
the application of the voltage to the gate stripes modifies the spin-wave
propagation and leads to the formation of band gaps in the spin-wave spectrum.
The band gaps are dynamically controllable, i.e. it is possible to switch band
gaps on and off within a few nanoseconds. The width and the center frequency of
the band gaps is defined by the applied voltage. At last, it is shown that the
application of the voltage to selected, rather than to all gate stripes allows
for a pre-defined modification of the band gap spectra. The proposed
voltage-controlled reconfigurable magnonic crystal opens a new way to low power
consumption magnonic applications.
