[14p-B414-1~9] Nano-Materials Science for MIR-THz photonics

▲ [14p-B414-7] THz Devices using Graphene, Topological Insulator, and Magnetic Heterostructures

〇Hyunsoo Yang¹ (1.National Univ. of Singapore)

Keywords:THz, Graphene, Magnetic Heterostructures

We first demonstrate THz modulators based on graphene/ionic liquid/graphene sandwich structures. The modulation covers from 0.1 to 2.5 THz with the modulation depth of up to 99%. We also report a tunable THz reflector using graphene/ionic liquid structures. The reflectance is modulated from 0.79% to 33.4%, and the reflection tuning is uniform (0.1 – 1.5 THz). In addition, we fabricate THz phase shifters based on thin liquid crystal cells sandwiched by two graphene layers. Topological insulator based THz modulators will be also introduced. Finally, we show a THz emitter based on ferromagnetic/nonmagnetic heterostructures. Our THz emitter has a peak intensity exceeding 500 μm thick ZnTe crystals. We have also fabricated the devices on flexible substrates, and demonstrated that it can be driven by low power fiber lasers. By integrating our spin based THz emitter with a photoconductive antenna, 2–3 order enhancement of the THz signals in a lower THz frequency range is achieved.