6/11/2024
From Lab to Limelight: PhD Candidates Take Gold and Silver at MRS
Gold and silver aren’t just for the Olympics. While two PhD candidates didn’t receive medals, they still have the honor of declaring themselves Graduate Student Award winners.
At the 2024 Materials Research Society (MRS) Spring Meeting, MatSE PhD candidate Jie Zhao and MechSE PhD candidate Shahriar Muhammad Nahid were awarded the Gold and Silver Graduate Student Award honors respectively. They were two of sixteen finalists for the awards, with six applicants receiving gold, and ten receiving silver.
The MRS Graduate Student Awards honor and encourage graduate students whose academic achievements and current materials research display a high level of excellence and distinction. The award application is open to students who have authored or co-authored an abstract submitted for that particular MRS meeting. The MRS GSA is a prestigious and competitive award and a majority of past awardees have joined top-tier institutions as faculty members or leading researchers.
Jie Zhao
Gold Medal Graduate Student Award
Jie Zhao was awarded the Gold Medal Graduate Student award for his contribution on Nanocalorimetry study of thin-film phase-change memory (PCM). PCM is a promising candidate for future applications in artificial intelligence (AI).
"If the phase change memory is successful, it can potentially combine the CPU and memory device together," said Zhao. "Each memory cell can be used as a building block for neural networks, which is a fundamental path to realize AI."
Using Nanocalorimetry, a technique his advisor, Assoc. Prof. Emeritus Leslie Allen’s group pioneered, Jie resolved the ten-year debate about the crystallization growth velocity of PCM, and developed an exceedingly high Nanocalorimetry scanning rate of 3,000,000 K/s, one hundred times higher than conventional calorimetry tools. He also performed the first calorimetry measurement on 2D vdW superlattice while working with Stanford's PCM device group (Prof. Pop’s group), thus providing fresh thermodynamic insights into the origin of energy efficiency in superlattice devices. This 2D thermodynamic study is funded by NSF-SSMC.
Zhao said he was surprised to learn he earned the gold medal award, as he was impressed with the research other finalists presented. In the meantime, he realized this was an opportunity to teach others about this method to explore its potential application in other thin-film electronics.
"Nanocalorimetry is actually a very unique technique. It can measure a monolayer of atoms on the surface. Such a sensitive technique, but no one in the PCM world had heard of it," Zhao explained.
That isn't the case any longer. Allen and Zhao have received requests for collaborations on Nanocalorimetry from companies and universities.
Zhao plans on graduating this winter and intends on contributing to future semiconductor by pursuing a position in either academia or industry.
Shahriar Muhamad Nahid
Silver Medal Graduate Student Award
Shahriar Muhammad Nahid was awarded the Silver Graduate Student Award for his work on ferroelectricity in 2D materials. Typical ferroelectric materials are three dimensionally bonded. While these 3D ferroelectrics are useful for many applications such as in low-powered electronics and non-volatile memory, they also face some limitations.
"If you're thinning down 3D ferroelectric material to say, only 10s of nanometers, then often the ferroelectricity becomes unstable. This is mainly due to the surface dangling bonds. However, 2D ferroelectrics don’t have the surface bonds, so they are stable, even in less than a nanometer thickness," said Nahid.
Nahid’s doctoral research focuses on how 2D materials and their unique properties can be utilized to overcome the challenges of 3D ferroelectrics. At the MRS Spring Meeting, he presented his work on the photovoltaic effect of 2D ferroelectric materials.
“For more than 50 years, people have known about the photovoltaic effect in ferroelectrics. But, still, there is an open question about its origin. And it is pretty important if you want to design self-powered electronic devices based on ferroelectric materials,” said Nahid.
Nahid, under the supervision of his advisors, Professor Arend van der Zande and Professor SungWoo Nam (now at University of California, Irvine), experimentally identified that the depolarization field is the underlying mechanism for the ferroelectric photovoltaic effect in a 2D ferroelectric material, α-In2Se3. This work was recently published in ACS Nano.
Nahid wants to build his career in academia and continue conducting research in nanoscience.