Mengxun Bai

I am currently a Research Fellow at the Molecular Beam Epitaxy (MBE) Group at University College London, focusing on advanced optoelectronic device design and semiconductor physics modeling. I hold a PhD in electrical and electronic engineering, with deep expertise in carrier transport simulations, photodetector physics, and III-V heterostructures.

My work involves extensive analysis of physical principles, numerical modeling, and scientific writing. With a deep understanding of applied physics and strong English academic communication skills, I am eager to contribute to AI training projects requiring high-level subject expertise in physics-related domains.

I have applied AI-assisted modeling and data analysis to better understand complex semiconductor physics, gaining firsthand insight into both the capabilities and limitations of AI-generated outputs. I’m eager to further integrate AI into physics research and contribute my domain expertise to improving the accuracy of large language models in applied physics.

• Modelling study of carrier transport in GaN/AlGaN superlattices

Modeling III-V nitrides and their heterojunction structures, analyzing carrier transport characteristics, and optimizing potential issues in High Electron Mobility Transistor

• Development of Tamm-assisted metasurface emitting laser (TAMSEL)

Participated in the design and preparation of a new kind of vertically emitting laser. Combining Tamm optical states with commercial VCSEL(GaAs) with working wavelengths of 940nm and 1300nm.

• C-band quantum-dot lasers on monolithically grown Si platform

The main goal of this project is to develop 1550-nm quantum dot materials and devices on Si or SOI substrates using group IV and III-V MBE reactors.

• Ge/GaAs uni-traveling carrier photodetector（UTC-PD）

This project aims to design and develop UTC-PD based on Ge/GaAs platform. Front-illuminated and waveguide designs are given, with complete simulation design and some fabricated devices

• Ge/GaAs Avalanche Photodiode (APD)

This project aims to design and develop APD based on Ge/GaAs platform. The structural design with high bandwidth and gain-bandwidth product is simulated and presented

-Published Journal-

Name: A Modelling study of Electron transport in GaN/AlGaN superlattices using Monte Carlo simulation https://doi.org/10.1002/pssb.202300384

Name: A Modelling study of hole transport in GaN/AlGaN superlattices https://doi.org/10.1038/s41598-023-4345-9

Name: Modelling and optimization of Ge/GaAs uni-travelling carrier photodiodes https://doi.org/10.1038/s41598-025-93960-z

Name: Antiphase boundary-free III–V materials epitaxially grown on on-axis silicon (001) substrates by ultra-thin silicon buffer https://doi.org/10.1063/5.0259915

-Conference-

SIOE 2022, Presentation, Cardiff

UK Semiconductors 2022, Poster, Sheffield

SIOE 2023, Presentation, Cardiff

ELSE 2023 Presentation, Glasgow

UKNC 2024, Presentation, Glasgow

META 2024, Presentation, Japan

• Semiconductor Materials and Device Design: Proficient in III-V semiconductor materials and device structure.
• Modelling & Simulation: Expertise in material and device modelling, Proficient in MATLAB, COMSOL, Lumerical, Nextnano, Silvaco TCAD and CST.
• Optical Measurements: Experience in constructing and using Fourier optical microscopes and spectrometers with Labview control.
• Electrical test and analysis: Basic I-V curve test, C-V curve test, Four-Point Probe, Hall Effect Measurement
• Clean Room: Knowledge in photolithography, dry etching, Metallisation, and wire bonding, especially for III-V semiconductors(main experience related to GaAs)
• Material Growth Technologies: Learned about PECVD and Molecular Beam Epitaxy.
• Film and Wafer Characterisation Analysis： SEM, AFM, FIB, Raman spectroscopy