Liwei Lin (Advisor)

Research Advised by Professor Liwei Lin

Lin Group:  List of Projects | List of Researchers

Declan M. Fitzgerald

Graduate Student Researcher
Mechanical Engineering
Professor Liwei Lin (Advisor)
Ph.D. 2029 (Anticipated)

Declan is a PhD student studying mechanical engineering in Professor Liwei Lin's research group. Prior to joining BSAC and the Berkeley community, he earned his BS/MS in mechanical engineering and his BS in psychology at the University of Maryland, College Park (UMD). He performed research in UMD's Bioinspired Advanced Manufacturing laboratory, as well as in the Division of Biomedical Physics at the Food and Drug Administration. His ongoing interests involve the use of advanced micro/nanofabrication techniques for the development of medical devices.

Huicong Deng

Graduate Student Researcher
Mechanical Engineering
Professor Liwei Lin (Advisor)
Professor Ming C. Wu (Advisor)
Ph.D. 2029 (Anticipated)

Huicong Deng received his B.E. in Electrical Engineering from University of Chinese Academy of Sciences in 2024. He is currently pursuing a Ph.D. degree in Mechanical Engineering, co-advised by Prof. Liwei Lin and Prof. Ming C. Wu. His research interest includes MEMS, integrated photonics and PMUTs.

3D Imaging via Four PMUT Receivers by Compressed Sensing

Nikita Lukhanin
Divij Muthu
Chaoying Gu
Megan Teng
Kamyar Behrouzi
Chun-Ming Chen
Laura Waller
Liwei Lin
2026

We have successfully demonstrated three-dimensional (3D) ultrasound imaging via compressed sensing using piezoelectric micromachined ultrasonic transducers (pMUTs). This work reports the first experimental demonstration of compressed sensing with pMUTs, achieving 3D image reconstruction near the acoustic wavelength limit by only four receiving elements. Pseudo-random transmission signatures were encoded through frequency and delay modulation to enable high-fidelity reconstruction with a peak signal contrast of 28.7 dB. A 16-element lithium-niobate pMUT array operating at a resonant...

Ultra-Sensitive Nanosensor for Rapid Detection of PFAS in Simulated Drinking Water

Nikita Lukhanin
Keming Bai
Mia Wang
Declan M. Fitzgerald
Grigory Tikhomirov
Liwei Lin
2026

Per- and polyfluoroalkyl substances (PFAS) are a class of persistent synthetic compounds, often called “forever chemicals,” that pose a significant threat to public health and the environment. Standard detection methods primarily rely on liquid chromatography and mass spectrometry [1], which is expensive, time-intensive, and requires trained personnel and laboratory infrastructure. While emerging approaches using metal-organic frameworks (MOFs), molecularly imprinted polymers, and lateral flow assays have been explored, they have yet to provide a solution that simultaneously offers part-...

BPNX1069: Programmable Self-Assembly of Microparticles (New Project)

Umut Can Yener
Declan M. Fitzgerald
Mostafa Sedky
Huicong Deng
2026

Piezoelectric micromachined ultrasonic transducer (PMUT) arrays provide a compact and scalable platform for synthesizing programmable acoustic pressure fields. In this project, we investigate PMUT-enabled programmable microparticle self-assembly in fluidic environments using dynamically controlled ultrasonic standing waves. Unlike conventional cymatics, which relies on fixed vibrational modes of a single acoustic source, individually addressable PMUT elements enable active control of frequency, phase, and amplitude to generate reconfigurable pressure landscapes. By tailoring...

Alexander Alvara

Graduate Student Researcher
Mechanical Engineering
Electrical Engineering and Computer Sciences
Professor Liwei Lin (Advisor)
Professor Kristofer S.J. Pister (Advisor)
Ph.D. 2025 (Anticipated)

Alexander Alvara is a final year Ph.D. Candidate in mechanical engineering who earned his 3 BS degrees from UC Irvine '17 concurrently in mechanical engineering, aerospace engineering, and materials science and engineering. Alexander is interested in extreme conditions applications and performance of MEMS devices as well as nanoscale materials engineering that investigates the interplay of materials with electromagnetism and light.

BPNX1061: Imaging Using PMUTs (New Project)

Nikita Lukhanin
Divij Muthu
Mostafa Sedky
Megan Teng
Tofic Esses
Linda Liu
Suraj Chamakura
Ryan Johnson
Chun-Ming Chen
2026

We use PMUTs for imaging.

Project is currently funded by: Member Fees

BPNX1036: Enhanced Gas Sensing with Machine Learning

Yuan Gao
Wei Yue
2026

Accurate and real-time gas detection is crucial for applications ranging from environmental monitoring to industrial processes. Traditional methods are often limited by low accuracy, slow response times, and high costs. This project introduces a scalable machine learning fusion system that integrates sensor fusion techniques to enhance detection performance. With encoder-decoder architectures and a decision fusion model, our approach significantly improves the accuracy of carbon dioxide sensing, achieving a mean absolute percentage error (MAPE) of 2.97% while reducing response and recovery...

Roll-to-Roll Soft Hydrogel Li-ion Battery

Jong Ha Park
2025
Fall 2025 BSAC Research Review Presentation View Presentation View Slides Project:...

High-SPL and Low-Driving-Voltage pMUTs by Sputtered Potassium Sodium Niobate

Fan Xia
Yande Xia
Sedat Pala
Ryuichi Arakawa
Wei Yue
Pei-Chi Tsao
Chun-Ming Chen
Hanxiao Liu
Megan Teng
Jong Ha Park
Liwei Lin
2023

This work presents an air-coupled piezoelectric micromachined ultrasonic transducer (pMUT) with
high transmitting acoustic pressure by using sputtered potassium sodium niobate (K,Na)NbO3
(KNN) thin film with a high piezoelectric coefficient (e31 ~ 8-10 C/m2) and low dielectric constant
(er ~ 260-300) for the first time. The fabricated KNN pMUT with a resonant frequency at 104.5 kHz
has been tested to exhibit unprecedented results: (1) high sound pressure level (SPL) of 109 dB/V
at a distance of 10 cm, which is 8 times higher than that of AlN-based pMUTs at a similar
...