Work

Waveguide-coupled uni-traveling-carrier lateral photodetector with Gaussian gradient germanium doping and DBR

Year: 2025

Type: article

Abstract: To address the demands of microwave photonic links for broadband and high dynamic range. We propose a germanium(Ge) waveguide-coupled uni-traveling-carrier lateral photodetector (UTC-L PD) targeting performance degradation constraint between bandwidth and saturation power under high optical input power. This PD utilizes Gaussian gradient doping to form a partially depleted absorber(Ge), blocking photogenerated electron diffusion while avoiding hole accumulation. The structure achieves up to 70 GHz bandwidth and maintains a 25 GHz high-speed response under 10 mW optical input power. The saturation power reaches approximately 30 mW. We further designed a distributed Bragg reflector (DBR) structure along the light propagation direction to enhance responsivity by fully utilizing optical absorption, achieving a high responsivity of 0.77 A/W at -3 V bias.

Source: Optics Express

DOI: 10.1364/oe.572565

Authors: Yiming Wang, Wei Ji, Jia Zhao

Institution: Shandong University

Language: English

Topic: Advanced Photonic Communication Systems

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,270

Funders: National Natural Science Foundation of China, Natural Science Foundation of Shandong Province, National Key Research and Development Program of China