  We experimentally demonstrate intensity and phase modulation of terahertz
radiation using actively controlled large-area planar metamaterial (metafilm)
hybridized with a 12 um thick layer of a liquid crystal. Active control was
introduced through in-plane electrical switching of the liquid crystal, which
enabled us to achieve a reversible single-pass absolute transmission change of
20 % and a phase change of 40 deg at only 20 V.
