[19p-A310-1~13] 4.2 Photonics Devices, Photonic Integrated Circuit and Silicon Photonics

13:45 〜 14:00奨励賞エントリー英語発表

[19p-A310-3] Hybrid silicon all-optical switching devices integrated with two-dimensional materials

〇Daiki Yamashita^1,2, Nan Fang¹, Shun Fujii^1,3, Yuichiro Kato¹ (1.RIKEN, 2.AIST, 3.Keio Univ.)

キーワード：

Silicon photonics、2D Materials

Here we propose hybrid all-optical switching devices that combine silicon nanocavities and two-dimensional semiconductor materials. By exploiting the refractive index modulation caused by photo-induced carriers in the two-dimensional material instead of the silicon substrate, we have overcome the limit of switching speed restricted by the carrier lifetime of silicon. Air-mode photonic crystal nanobeam cavities capable of efficient interaction with two-dimensional materials are fabricated, and molybdenum ditelluride, a two-dimensional material with a rapid carrier recombination, is transferred onto the cavities. A thin molybdenum ditelluride flake loaded on a cavity is excited by an optical control pulse to shift the resonant wavelength of the cavity for switching operation. We have successfully implemented a high-speed (~30 ps) all-optical switching with low-excitation energy (~500 fJ). The switching speed has improved by ~10² times compared to devices without two-dimensional materials.