Provided is a bulk acoustic resonator (BAR)-based resonant structure in relation to electric and radio technologies, and more particularly, to a wireless power transmission system. A resonant apparatus for wireless power transmission may include a conducting loop, and a high quality capacitor. The high quality capacitor may include a metacapacitor including a thin piezoelectric layer disposed between two metal electrodes. The metacapacitor may be disposed between two dielectric layers of which central portions are etched, and the conducting loop may be disposed on an upper layer of the two dielectric layers.