Active terahertz nanoantennas based on VO2 phase transition.
Unusual performances of metamaterials such as negative index of refraction, memory effect, and cloaking originate from the resonance features of the metallic composite atom(1-6). Indeed, control of metamaterial properties by changing dielectric environments of thin films below the metallic resonators has been demonstrated(7-11). However, the dynamic control ranges are still limited to less than a factor of 10,(7-11) with the applicable bandwidth defined by the sharp resonance features. Here, we present ultra-broad-band metamaterial thin film with colossal dynamic control range, fulfilling present day research demands. Hybridized with thin VO(2) (vanadium dioxide) (12-18) films, nanoresonator supercell arrays designed for one decade of spectral width in terahertz frequency region show an unprecedented extinction ratio of over 10000 when the underlying thin film experiences a phase transition. Our nanoresonator approach realizes the full potential of the thin film technology for long wavelength applications.
Seo
Minah
M
Center for Subwavelength Optics and Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
Kyoung
Jisoo
J
Park
Hyeongryeol
H
Koo
Sukmo
S
Kim
Hyun-sun
HS
Bernien
Hannes
H
Kim
Bong Jun
BJ
Choe
Jong Ho
JH
Ahn
Yeong Hwan
YH
Kim
Hyun-Tak
HT
Park
Namkyoo
N
Park
Q-Han
QH
Ahn
Kwangjun
K
Kim
Dai-sik
DS