This article was updated on July 26, 2023.
Seven assistant professors in the George R. Brown School of Engineering at Rice University have received National Science Foundation (NSF) CAREER Awards in 2023.
They are Songtao Chen, electrical and computer engineering (ECE); Taiyun Chi, ECE; Yimo Han, materials science and nanoengineering (MSNE); Kaiyu Hang, computer science (CS); Lauren Stadler, civil and environmental engineering; Todd Treangen, computational biologist and assistant professor of CS; and Hanyu Zhu, MSNE.
The awards from the National Science Foundation are given annuvally to some 400 young scientists and engineers in the U.S. in support of “early career faculty who have the potential to serve as academic role models in research and education and to lead advances in the mission of their department or organization.”
In 2022, a record eight engineering faculty members from Rice received CAREER Awards, along with four members of the Wiess School of Natural Sciences faculty.
With his five-year, $750,000 grant, Chen will advance development of quantum networks by leveraging imperfections, known as point defects, in silicon material.
He studies how quantum-level interactions between light and matter can help remove barriers limiting large-scale implementation of quantum communication and computing, which could help address problems in medicine, cybersecurity, artificial intelligence and engineering.
Chen’s research focuses on how the interaction between photons and T centers, a recently identified type of point defect in silicon, can be used for quantum information applications.
“Atoms in solid-state silicon are organized in a perfect lattice,” Chen said. “The T center is a point defect in the regularity of this lattice. This defect has a spin component that we can use to build qubits and an optical component that can be exploited to interface with the spin. Research on the coherent control, measurement and entanglement of T center qubits could help turn them into building blocks of quantum network nodes.”
One of the most challenging aspects of quantum communication that Chen hopes to address is signal-loss during transmission.
“Whenever the photons that make up an optical signal propagate in an optical fiber, some of them will get lost as they travel over a certain distance, meaning the signal grows weaker the longer it propagates. Signal-loss grows exponentially with distance,” said Chen, who hopes to develop T center-based silicon quantum photonic chips and build a fully functional quantum information processing system.
Chi will use his $500,000 grant to fund development of an implanted neural interface with neural recording channel counts more than 10 times higher than current state-of-the-art technology. He will also develop a noninvasive deep-brain-stimulation system based on temporally interfering electromagnetic waves.
Neural interfaces are tools for better understanding the brain, and are used increasingly in clinical applications. Emerging brain-machine interfaces built on large-scale neural recording, for instance, can decipher brain activities. The decoded information can be used to control neural prosthetics to restore lost sensory or motor functions for paralyzed patients.
In addition, deep brain stimulation has proven effective in treating certain disorders by injecting a pulsed current with a predefined pattern.
“These results are highly encouraging,” Chi said, “but to fully unlock the potential of neural interfaces for future human clinical use, new device capabilities need to be developed with significantly improved hardware performance. The goal is to have an impact on the designs in future brain-machine interfaces, neural prostheses and the treatment of brain disorders.”
With her five-year, $650,707 grant, Han will use recent electron microscopy approaches to observe the deformation mechanisms of 2D materials and help understand their differences from conventional behavior observed in bulk materials.
“Two-dimensional films under strain become deformed,” she said. “Deformation and defects play a critical role in the mechanical, electrical and chemical properties of these materials because of their atomic thinness. We want to leverage this knowledge when we are engineering new applications for 2D materials.”
Han uses the microscopes housed in the Electron Microscopy Center in Brockman Hall. She hopes to advance the use of complex 2D materials in such applications as flexible electronics, quantum computing, catalysis and protective coatings. Using four-dimensional scanning transmission electron microscopy and related techniques, she hopes to map the lattice strain and deformations in 2D structures.
“By investigating various sizes and shapes of 2D structures,” Han said, “we expect to gain a more comprehensive understanding of novel deformation mechanisms in complex 2D materials. This will enable precise engineering of strain and defects in these materials and structures, which will have significant implications for development of more advanced devices.”
Hang will use his $600,000 award to develop robots that can manipulate unfamiliar objects in high-uncertainty situations. His project aims to develop general-purpose robots that can handle complex physical interactions in real-world settings without requiring perfect input from sensors or extensive instructions.
“My research is focused on robot manipulation,” Hang said. “And when we talk about robot manipulation, we’re referring to physically using the robot to change the configuration of the world.”
Making robots more dexterous in real time ⎯ i.e. better at manipulating unfamiliar objects and navigating complex, real-world situations and environments ⎯ requires improving their computational ability to carry out finely-tuned, fine-grained actions that are context-specific and self-correcting.
“Imagine having a robot that can clean surfaces in the home or in a hospital setting that is able to decide what cleaning motion or force to apply, depending on the type of object or area it encounters,” Hang said. “Instead of designing specific robots for specific tasks ⎯ which works well in an industrial setting where you actually have control over the working environment ⎯ I hope to develop robots that can perform daily tasks in new or unfamiliar environments that are constantly changing.”
Hang says recent advances in computational power and an increased supply of robots that incorporate compliant design enable him to carry out his vision.
“This is the right time to take on this project,” Hang said. “If we’d wanted to do this five or 10 years ago, we wouldn’t have been able to.”
Stadler earned a five-year, $553,597 grant for her proposal to modify microorganisms and use them to treat wastewater. Her plan concentrates on engineering bacteria and will exploit a technique known as horizontal gene transfer (HGT), the movement of genetic material between microorganisms rather than the transmission of DNA from parent to offspring.
“If harnessed properly, HGT could be used to precisely engineer microbiomes for environmental bioremediation, the inactivation of microbial pathogens or the recovery of valuable chemicals from wastewater,” Stadler said. The mechanisms that drive these transfers are not fully understood.
“Our goal is to advance our ability to precisely engineer microbial communities. One application we plan to study is the manipulation of a wastewater treatment microbial community so it more efficiently produces certain useful compounds, such as volatile fatty acids. These are precursors that can be converted to valuable products such as bioplastics and biofuels,” Stadler said.
Treangen’s five-year, $599,943 award is funded by the Division of Information and Intelligent Systems within the NSF Directorate for Computer and Information Science and Engineering. His research will focus on developing computational approaches for identifying and characterizing microbial DNA not previously observed.
“We are in the golden age of our ability to read and write DNA. The sequencing of genomic data found in nature is now democratized, opening the door to a digital library of countless documents of evolutionary history,” Treangen said. “For SARS-CoV-2 alone there are now over 15 million genomes, and there are multiple petabytes of data available for download from the publicly accessible Sequence Read Archive (SRA).”
By leveraging this mass of publicly available data in the SRA, Treangen will pioneer new approaches for pathogen detection and monitoring by using scalable and accurate computational strategies. The work will employ existing approaches to biosurveillance coupled with innovative computational approaches.
The computational approaches will be combined into a platform being created by Treangen called GuarDNA. “It will integrate everything into the first-of-its-kind comprehensive platform designed for genomics-based biosecurity and biosurveillance,” he said.
Zhu received a five-year, $653,000 grant from the NSF for his proposal, “Probing Quantum Materials Modified by Terahertz Quantum Fluctuations.”
“Such fluctuations are usually negligible in daily life, though theoretically they can grow large when we reduce the wavelength of standing waves and pack many possible waves into a very small volume,” Zhu said. “No need for energy to create new waves, but just collect existing waves from the vacuum.”
According to recent theoretical and experimental research, such fluctuating waves may be sufficiently powerful to change such properties of materials as atomic structure, electrical conductivity and magnetism. Zhu hopes to answer some of these fundamental questions in what he calls “this new paradigm of fluctuation-modified materials.”
“We intend to leverage the natural mixture of electromagnetic waves and atomic vibrations – called phonon-polaritons – in many ionic crystals,” Zhu said. “Near the vibrational resonance, which is in the terahertz frequencies, the wavelength of the mixed wave shrinks so the quantum fluctuation will be enhanced.”
Zhu plans to measure the fast quantum fluctuation of the light and matter inside micrometer-scale volumes at near absolute zero temperatures and track the modified energy evolution and properties of the materials. He expects the results to provide insights into optimizing materials by harvesting quantum forces.