Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission(EOT)in the terahertz(THz)region,whereby a giant forward light propagation can be created using constructiv...Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission(EOT)in the terahertz(THz)region,whereby a giant forward light propagation can be created using constructive interference of tunneling surface plasmonic waves.However,numerous applications of THz meta-devices demand an active manipula-tion of the THz beam in free space.Although some studies have been carried out to control the EOT for the THz region,few of these are based upon electrical modulation of the EOT phenomenon,and novel strategies are required for act-ively and dynamically reconfigurable EOT meta-devices.In this work,we experimentally present that the EOT resonance can be coupled to optically reconfigurable chalcogenide metamaterials which offers a reversible all-optical control of the THz light.A modulation efficiency of 88%in transmission at 0.85 THz is experimentally observed using the EOT metama-terials,which is composed of a gold(Au)circular aperture array sitting on a non-volatile chalcogenide phase change ma-terial(Ge2Sb2Te5)film.This comes up with a robust and ultrafast reconfigurable EOT over 20 times of switching,excited by a nanosecond pulsed laser.The measured data have a good agreement with finite-element-method numerical simula-tion.This work promises THz modulators with significant on/off ratios and fast speeds.展开更多
Metasurface analogue of the phenomenon of electromagnetically induced transparency(EIT)that is originally observed in atomic gases offers diverse applications for new photonic components such as nonlinear optical unit...Metasurface analogue of the phenomenon of electromagnetically induced transparency(EIT)that is originally observed in atomic gases offers diverse applications for new photonic components such as nonlinear optical units,slow-light devices,and biosensors.The development of functional integrated photonic devices requires an active control of EIT in metasurfaces.We demonstrate a reversible switching of the metasurface-induced transparency in the near-infrared region by incorporating a nonvolatile phase change material,Ge2Sb2Te5,into the metasurface design.This leads to an ultrafast reconfigurable transparency window under an excitation of a nanosecond pulsed laser.The measurement agrees well with both theoretical calculation and finite-difference time-domain numerical simulation.Our work paves the way for dynamic metasurface devices such as reconfigurable slow light and biosensing.展开更多
文摘Metamaterials composed of metallic antennae arrays are used as they possess extraordinary optical transmission(EOT)in the terahertz(THz)region,whereby a giant forward light propagation can be created using constructive interference of tunneling surface plasmonic waves.However,numerous applications of THz meta-devices demand an active manipula-tion of the THz beam in free space.Although some studies have been carried out to control the EOT for the THz region,few of these are based upon electrical modulation of the EOT phenomenon,and novel strategies are required for act-ively and dynamically reconfigurable EOT meta-devices.In this work,we experimentally present that the EOT resonance can be coupled to optically reconfigurable chalcogenide metamaterials which offers a reversible all-optical control of the THz light.A modulation efficiency of 88%in transmission at 0.85 THz is experimentally observed using the EOT metama-terials,which is composed of a gold(Au)circular aperture array sitting on a non-volatile chalcogenide phase change ma-terial(Ge2Sb2Te5)film.This comes up with a robust and ultrafast reconfigurable EOT over 20 times of switching,excited by a nanosecond pulsed laser.The measured data have a good agreement with finite-element-method numerical simula-tion.This work promises THz modulators with significant on/off ratios and fast speeds.
基金supported by the International Science and Technology Cooperation Program of China(Grant No.2015DFG12630)support from LiaoNing Revitalization Talents Program(Grant No.XLYC1807237)
文摘Metasurface analogue of the phenomenon of electromagnetically induced transparency(EIT)that is originally observed in atomic gases offers diverse applications for new photonic components such as nonlinear optical units,slow-light devices,and biosensors.The development of functional integrated photonic devices requires an active control of EIT in metasurfaces.We demonstrate a reversible switching of the metasurface-induced transparency in the near-infrared region by incorporating a nonvolatile phase change material,Ge2Sb2Te5,into the metasurface design.This leads to an ultrafast reconfigurable transparency window under an excitation of a nanosecond pulsed laser.The measurement agrees well with both theoretical calculation and finite-difference time-domain numerical simulation.Our work paves the way for dynamic metasurface devices such as reconfigurable slow light and biosensing.