Symposium NM03: Topological and Quantum Phenomena in Intermetallic Compounds and Heterostructures

Sahal Kaushik, Stony Brook University

Late News: Tunable Chiral Symmetry Breaking in Symmetric Weyl Materials

Written by Jessalyn Hui Ying Low

Asymmetric Weyl materials have an inherently chiral crystal structure, but lack symmetry between left- and right-handed fermions. Due to these properties, they exhibit many unique phenomena such as the quantized circular photogalvanic effect, yet are much rarer as compared to symmetric Weyl materials. In this talk, Sahal Kaushik shows how by applying external perturbations, in particular external magnetic field, chiral symmetry in symmetric Weyl materials can be broken to become asymmetric.

With a focus on materials with the -43m (Td) point group, Kaushik explains that for chiral symmetry breaking, it is insufficient to break only reflection symmetries as this could induce false chirality. Rather, all combinations of reflection and time reversal should be broken. Therefore, for a measure of true chirality, the magnitude of the magnetic field must be different along all three directions, implying that chirality will be broken when the magnetic field is applied along low symmetry directions like [147] and not high symmetry directions like [001] and [111]. It was shown that when magnetic field was applied along low symmetry directions, left- and right-handed Weyl cones indeed showed different energies, velocities, and tilts. These symmetry breaking parameters were influenced by magnitude and direction of the magnetic field. Notably, as the direction of magnetic field increased in asymmetry, the discrepancy between left- and right-handed Weyl cones increased, highlighting how chirality symmetry breaking in Weyl materials can be tuned.


Congratulations to the 2021 Virtual MRS Spring Meeting Science as Art Winners!

First Place


2021 Spring Meeting Graduate Student Awards

The MRS Graduate Student Awards are intended to honor and encourage graduate students whose academic achievements and current materials research display a high level of excellence and distinction. In addition to the MRS Graduate Student Gold and Silver Awards, the Arthur Nowick Graduate Student Award, which honors the late Dr. Arthur Nowick and his lifelong commitment to teaching and mentoring students in materials science, will be presented to a GSA finalist who shows particular promise as a future teacher and mentor.

Gold 

 

Chullhee Cho
Chullhee Cho

University of Illinois
at Urbana-Champaign

Ahyoung Kim
Ahyoung Kim
University of Illinois
at Urbana-Champaign

Joeson Wong
Joeson Wong
California Institute of Technology

Guomin Zhu
Guomin Zhu
University of Washington

 

Silver 

Jingshan S. Du
Jingshan S. Du
Northwestern University

Nikita Dutta
Nikita Dutta (Nowick Prize)
Princeton University

Zhiwei Fang
Zhiwei Fang
The University of Texas at Austin

Hanson Wang
Hansen Wang
Stanford University

 

Hanson Wang
Jiayue Wang
Massachusetts Institute of Technology

Wanghuai Xu
Wanghuai Xu
City University of Hong Kong

MRS acknowledges the generous contribution for the Nowick Award to the MRS Foundation from Joan Nowick in memory of her husband Dr. Arthur Nowick.


Best Poster Winners–2021 Virtual MRS Spring Meeting

Hector Mandujano, The University of Texas at El Paso, (CT04.01.06)

Changho Hon, Seoul National University, (CT05.14.05)    

Yunseul Kim, Gwangju Institute of Science and Technology, (EL01.10.15)

Daniel Davies, University of Illinois at Urbana-Champaign, (EL01.14.10)  

Jingjing Shi, Georgia Institute of Technology, (EL04.13.07)             

Wonjin Choi, University of Michigan–Ann Arbor, (EL05.13.03)     

Komalika Rani, Université Paris-Saclay, (EL09.07.01)        

Sang Seob Lee, Yonsei University, (EN01.08.05) 

Alessia Fortunati, Politecnico di Torino, (EN02.01.06)      

Virgil Andrei, University of Cambridge, University of Cambridge, (EN02.06.03)     

Eman Alhajji, King Abdullah University of Science and Technology, (EN03.08.01) 

Teresa Cristina Rojas, Instituto de Ciencia de Materiales de Sevilla, (EN05.03.04)

Davide Moia, Max Planck Institute for Solid State Research, (EN06.10.08)              

Eric Chang, Duke University, (EN07.04.04)            

Albanie Hendrickson-Stives, The Pennsylvania State University, (NM05.04.05)    

Hyoung Taek Kim, Sungkyunkwan University, (NM09.10.02)        

Chunhong Dong, Georgia State University, (SM01.03.03)               

Sebastian Buchmann, KTH Royal Institute of Technology, (SM03.01.06)  

Jeong Eun Park, Inha University, (SM05.06.05)   

Jisoo Jeon, Inha University, Inha University, (SM07.08.09)             

Che-Hsuan Cheng, University of Michigan–Ann Arbor, (ST01.07.07)          

Hojang Kim, Korea Advanced Institute of Science and Technology, (ST01.11.06)  

Kooknoh Yoon, Seoul National University, (ST04.04.07)


Symposium X: Frontiers of Materials Research

Symposium X—Frontiers of Materials Research_yi-cuiYi Cui, Stanford University
Nanotechnology for Sustainability

Written by Sophia Chen

Yi Cui of Stanford University delivered a Symposium X lecture on Thursday. A materials scientist, Cui discussed nanotechnology applications in sustainability efforts, such as reduction of fossil fuel use and pandemic mitigation efforts. Just in his lab alone, they use nanotechnology to design better batteries, medical face masks, and clothing.

One thrust of his group’s research is “trying to reinvent the battery,” said Cui. Over the last 15 years, Cui’s group has tackled questions such as how to improve the energy density of batteries, how to extend their lifetime, how to reuse and recycle them, all while making sure the technology is safe. He sees his work as the next generation to lithium ion batteries, now in widespread use in portable electronics and electric vehicles, and whose pioneers received the Nobel Prize in 2019.

Cui has developed new batteries from higher energy density materials by optimizing the geometry of the materials inside the batteries. For example, his group has made lithium-ion batteries with anodes made of silicon nanowires instead of the conventional graphite. However, silicon poses design challenges, as it expands several times its original size as the battery discharges. This can cause the silicon nanowires to crack and break, so Cui’s group has developed a shell-like structure around the silicon to avoid the material fracturing. They have also made strides in developing lithium metal batteries—a “holy grail” for the field because of the metal’s theoretical energy density. But in reality, lithium metal is challenging to work with because the metal expands dramatically and breaks easily. To prevent this, Cui’s group has developed hollow nano-capsules for lithium metal to sit in.

His group has also developed new techniques for imaging the dynamics inside batteries. In 2016, they developed the technique of cryogenic electron microscopy, which freezes material and images the material at atomic-scale resolution.

Nanofibers can also make high quality air filters, such as those needed in medical face masks, said Cui. His group has achieved filters with 60% porosity made from fibers 10 µm in diameter, spaced apart by 15 µm. This produces a breathable mask using a tiny amount of material.

Clothing that cools or heats the wearer could also make a significant difference in energy consumption, said Cui. His group has designed a polyethylene textile that is more transparent to the infrared radiation produced by the human body compared to cotton. In tests, they found the material caused the wearer’s skin temperature to be nearly 3°C cooler than when the person was wearing cotton. He pointed out that changing heating or cooling by a single degree Celsius can, on average, alter energy usage by 10 percent.

It’s important to get these innovations in the hands of consumers quickly, said Cui. His company Amprius, founded in 2009, has commercialized the silicon nanowire anode battery technology. He has recently founded the startup Eenotech for commercializing the polyethylene material, whose spinoff company LifeLabs Design will sell a limited quantity of clothing made from the polyethylene material this summer.

At the end of 2020, Cui became the director of Stanford’s Precourt Institute for Energy. As director, Cui oversees a range of research spanning many fields. In addition to materials and other hard science research, the institute weaves together researchers studying sustainable finance, policy, human behavior, artificial intelligence, and more.

Symposium X—Frontiers of Materials Research features lectures aimed at a broad audience to provide meeting attendees with an overview of leading-edge topics.


Symposium SM11: Design and Analysis of Bioderived and Bioinspired Multifunctional Materials

Yeojin Jung, City College of New York

Programming Bombyx Mori Silk’s Water-Responsive Actuation Using Silica Nanoparticles

Written by Jessalyn Hui Ying Low

Spider silk is a water-responsive material found in nature and is known to be a great water-responsive actuator, but faces the issue of low availability. In this talk, Yeojin Jung shows how by engineering the Bombyx (B.) mori (silkworm) silk, water-responsiveness actuation can be enhanced, and even surpass that of natural muscles and spider silk. “Our findings could help apply natural silks as simple and scalable, but powerful water-responsive materials for practical applications,” says Jung.

Jung first explains that microstructure engineering can be used to increase the water-responsiveness of B. mori silk. By subjecting the silk to water vapor or methanol treatment, β-sheet crystallinity is increased. β-sheet nanostructures are capable of translating water energy into mechanical energy, thereby showing the potential for B. mori as actuators. Moreover, Jung shares that by adding stiff silica nanoparticles to mimic stiff β-sheet crystals, water-responsiveness could be significantly increased. Fourier-transform infrared spectroscopy (FTIR) studies additionally confirmed that the silica nanoparticles had minimal effect on the silk’s microstructure, with increase in water-responsiveness energy density due to the nanoparticles instead. With the addition of silica nanoparticles, water-responsiveness energy density of B. mori silk was found to be increased to ~ 700 kJ m-3, a value much higher than that of spider silk.


Symposium SM03: Advanced Neural Materials and Devices

Jihwan Lee, University of California, San Diego

High Density, Individually Addressable Silicon-Based Nanowire Arrays Record Native Intracellular Activity from Primary Rodent Neurons without Electroporation

Written by Arun Kumar

Jihwan Lee from the University of California, San Diego says that many questions regarding neurons can be answered by looking at intracellular recordings from neurons and the neuronal networks. High spatiotemporal resolution and minimal invasiveness are essential requirements for understanding altered neuronal functions during diseased conditions and their response to drugs. The prevalently used method for probing intracellular potentials, the patch-clamp technique offers high signal fidelity but is limited in its throughput, scalability, and invasiveness. Planar microelectrode arrays can provide high throughput and a highly scalable process but are limited in their low signal fidelity. On the other hand, vertical nanowire arrays present an innovative nanoscale device providing high fidelity, throughput, and scalability.

Unlike prior nanoelectrode processes, Jihwan Lee states that their process does not involve any optoporation/electroporative technique to transiently permeate the cells and measure the intracellular potentials. This potentially helps reduce the damage caused to the cells. He states that their arrays can measure the native recording of graded potentials without attenuation of the signal amplitude during the experimentation. Increasing spike activity was recorded by the sensors during primary rat neuronal cell development and maturation. Lee also shows how the recorded spike activity and frequency of spikes vary during the addition of drugs. Apart from neurons, effective action potential measurements were also made from cultured cardiovascular progenitor cells. The non-electroporative, non-optoporative, sharp-nanowire array for intracellular sensing applications could be a cost-effective screening method for studying neuronal dynamics and neurological disease pathology.


Symposium SM08: Next-Generation Materials and Technologies for 3D Printing and Bioprinting

Jingjun Wu, Zhejiang University

Soft Hydrogels as Anti-Adhesion Interfaces for Rapid Digital Light 3D Printing

Written by Jessalyn Hui Ying Low

Bottom-up digital light processing (DLP) is a vat polymerization technique commonly used for three-dimensional (3D) printing applications; however, printing speed is limited by the adhesion between the cured part and curing window, limiting applications in large-scale manufacturing. In this talk, Jingjun Wu reports the use of soft and deformable hydrogels to achieve solid-solid, but soft interface between the two parts, which will allow for reduced separation force and high printing speeds.

Wu explains that this is achieved by adding the hydrogel interface between the liquid resin and bottom glass window. By decreasing the modulus and increasing the thickness of the hydrogel, separation force can be decreased. Using this hydrogel interface, lower separation forces were achieved as compared to using fluorinated ethylene propylene (FEP) interface, which is the technique commercially used. This lower separation force was attributed to the ability for localized deformation induced separation in the hydrogel interface, unlike in FEP. Furthermore, it was found that using a printer equipped with such hydrogel interface allowed for a high printing speed as fast as 400 mm/h. Wu shares that these hydrogels exhibited mechanical stability during printing as well as good compatibility with the resin. Importantly, printing resolution is not compromised, therefore making 3D printers with these soft hydrogels favorable for achieving rapid 3D printing.


Symposium NM07: Beyond Graphene 2D Materials—Synthesis, Properties and Device Applications

Ruifang Zhang, Purdue University

Late News: Atomically-Thin Tellurene Based Biosensor for Selective and Sensitive Electrochemical Detection of Dopamine

Written by Arun Kumar

Similar to Alzheimer’s or other neurodegenerative disorders, Parkinson’s is a chronic progressive disease where treatment options rely on a faster diagnosis. Parkinson’s affects an estimated 60,000 Americans every year. But unlike Alzheimer’s, Parkinson’s disease cannot be categorized with a single confirmatory test. The general practitioner is often required to look at the presented symptoms and rule out other disorders. But, Parkinson’s can be critically sensed by the altered release profile of the neurotransmitter dopamine in patients.

Ruifang Zhang from Purdue University presents a novel tellurene-based electrochemical biosensor that can be used as a cheap, highly selective, and sensitive alternative to quantitate dopamine levels in human plasma. For fabrication, first, a two-dimensional (2D) tellurene layer is placed over a glassy carbon electrode by a drop-casting method. Secondly, a quick in situ reduction is performed by immersing the material into a gold precursor solution to deposit gold nanoparticles over the surface. The fabricated biosensor is highly sensitive to dopamine levels through the effective interaction between nitrogen atoms on dopamine and the active tellurene surface. She says that an over-deposition of gold nanoparticles on the surface can negatively impact the device performance owing to the lower availability of active tellurene. So, the device optimization is based on several factors such as gold reaction time, tellurene width, and chloroauric acid concentration. A cheap and sensitive tool such as the tellurene-based biosensor can help in faster measurements of dopamine level changes for the clinical diagnosis of neurological disorders.