Ye, Han; Han, Qin; Wang, Shuai; Chu, Yimiao; Zheng, Yu; Geng, Liyan Source: Applied Physics Express, v 17, n 1, January 1, 2024;

Abstract:

The upcoming beyond-5G and 6G ultra-high speed transmission networks have urged photonic transceivers to allow for higher bandwidth performance. In this work, an evanescent coupled high speed waveguide photodetector (PD) is fabricated and analyzed. Adopting a modified uni-traveling carrier structure, the PD exhibits a bandwidth of 100 GHz and a low dark current of 3 nA at ？1.5 V. Numerical simulations show that the measured responsivity of 0.25 A W is worsened by the inaccurate cleaving length of the coupling waveguide, and could potentially reach 0.688 A W with anti-reflection film at the facet. The bandwidth is bound by high resistance and capacitance giving a transit-time limit as high as 310 GHz.

？ 2023 The Author(s). Published on behalf of The Japan Society of Applied Physics by IOP Publishing Ltd. (27 refs.)