We demonstrate ultrafast all-optical control of terahertz (THz) radiation through nanoresonators, slot antennas with a hundred micron length but submicron width in thin gold layers, fabricated on vanadium dioxide (VO2) thin films. Our THz nanoresonators show almost perfect transmission at resonance. By virtue of phase transition of VO2 from insulating to metallic state, induced in subpicosecond time scale by moderate optical pump, ultrafast control of THz transmission is enabled. This is compared to bare VO2 films where no switching dynamics are observed under similar conditions.
Bibliographical noteFunding Information:
This work was supported by the Korea Science and Engineering Foundation (KOSEF) (SRC, Grant No. R11-2008-095-01000-0), the Korea Research Foundation (KRF), KICOS (GRL, Grant No. K20815000003), and Hi Seoul Science/Humanities Fellowship grant funded by the Korean Government (MEST) (Grant No. 2009-0071309), the Seoul R&BD Program (10543), and Seoul Scholarship Foundation.