Nonlinear multiferroic phase shifters for microwave frequencies

A nonlinear microwave phase shifter based on a planar multiferroic composite has been studied. The multiferroic structure is fabricated in the form of a bilayer consisting of yttrium iron garnet and barium strontium titanate. The principle of operation of the device is based on the linear and nonlinear control of the phase shift of the hybrid spin-electromagnetic waves propagating in the bilayer. The linear control is realized with magnetic and electric fields. The nonlinear control is provided by the input power of microwave signal. The device showed a nonlinear phase shift up to 250 degrees, electric field induced phase shift up to 330 degrees, and magnetic field induced phase shift of more than 180 degrees. (C) 2014 AIP Publishing LLC.