کنفرانس مهندسی برق ایران

صفحه اصلی / بیست و نهمین کنفرانس مهندسی برق ایران

Design of a highly efficient photoconductive terahertz modulator enhanced by photonic crystal resonant cavity

نویسندگان :

Faramarz Alihosseini¹ Zahra Heshmatpanah² Hesam Zandi³

1- دانشگاه صنعتی خواجه نصیرالدین طوسی 2- دانشگاه صنعتی خواجه نصیرالدین طوسی 3- دانشگاه صنعتی خواجه نصیرالدین طوسی

کلمات کلیدی :

modulator, photonic crystal, conductivity, modulation depth, modulation speed

چکیده :

We propose and numerically investigate an optically-controlled terahertz (THz) modulator based on photocarrier generation in GaAs, incorporated with photonic crystal cavity-waveguide coupling structure. Here, we demonstrate the intensity of THz traveling-wave can be tuned by varying the conductivity of the GaAs through an infrared optical pumping. This modulator benefits from strong interaction between THz wave and photoconductive material for achieving deep modulation with GHz modulation rate even with low pumping power. We analyze the device properties in time and frequency domains using the finite element method (FEM). Simulation results indicate that when the optical pump fluence is tuned from 3 nJ/cm2 to 10 nJ/cm2 this modulator can operate with a high modulation depth from 81.6% to 98.2% and also a high modulation rate up to 3 GHz for at 1 THz.