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Nature doesn't like having interfaces—this is why bubbles like to be round, and the surface of a pond settles to flat as long as it's not disturbed. These trends minimize the total amount of interface (or surface) that is present. As an exception to this behavior, certain materials are known to have a property, called negative stiffness, where the interface prefers to become distorted, or wavy, even without any external stimulation. Interfaces with negative stiffness have been considered in crystals before, but the characteristic has now also been found in modern magnetism.

The new Center for Reserach Computing (CRC), formerly known as the Center for Simulation and Modeling (SaM), is among the first in the nation to have access to Intel’s powerful new computing systems. The system will dramatically increase the speed of computation available to researchers through Pitt’s Center for Research Computing, said Ralph Roskies, associate vice provost for research computing.

Although scientists have for decades been able to synthesize nanoparticles in the lab, the process is mostly trial and error, and how the formation actually takes place is obscure. However, a study recently published in Nature Communications entitled "“Thermodynamic Stability of Ligand-Protected Metal Nanoclusters” by Giannis Mpourmpakis and PhD candidate Michael G. Taylor explains how metal nanoparticles form. The research, completed in Mpourmpakis’ Computer-Aided Nano and Energy Lab (C.A.N.E.LA.), is funded through a National Science Foundation CAREER award and bridges previous research focused on designing nanoparticles for catalytic applications.

Kevin Chen received $1.275 million to develop radiation-hard, multi-functional, distributed fiber sensors, and sensor-fused components that can be placed in a nuclear reactor core to improve safety and efficiency. The grant is from the Nuclear Energy Enabling Technologies (NEET) program as part of the DOE’s Nuclear Energy University Program (NEUP).

“This NEET grant will allow our lab to continue its partnerships with leading technological companies and national laboratories to develop solutions to some of the most pressing issues affecting nuclear energy production,” said Chen. “Advances in sensor technology can greatly enhance the sensitivity and resolution of data in harsh environments like a nuclear reaction, thereby improving safety operations.”

Congratulations to the 2017/2018 PQI Graduate Student Research Award Winners!

Ms. Lucy Chen (Levy Lab, Physics), Mr. Yanan Dai (Petek Group, Physics), Ms. Xing Yee Gan (Millstone Group, Chemistry), Mr. Kevin Gasperich (Jordan Group, Chemistry), Mr. Jianan (Arthur) Li (Levy Lab, Physics), and Mr. Li Zhi (Mong Group, Physics) won one term of graduate funding for the year 2017/2018.

In a joint experimental and theoretical study, Di Xiao and collaborators from several groups across the country and from China observed out-of-plane magnetism in a monolayer of chromium triiodide (CrI3). The study, entitled further described the dependence of the magnetic ordering on the number of layers in the material—bilayer CrI3 displays suppressed magnetization, whereas in trilayer CrI3 the interlayer ferromagnetism is restored. This thickness-dependent behavior is typical of van der Waals crystals. The findings are reported in an article entitled “Layer-dependent ferromagnetism in a van der Waals crystal down to the monolayer limit” that was published in this month’s issue of Nature. 

John Keith was among the Emerging Investigators in 2017 recommended by experts in the field of materials chemistry research in a themed issue of the Journal of Materials Chemistry A, published by the Royal Society of Chemistry. His article “Computational investigation of CO₂ electroreduction on tin oxide and predictions of Ti, V, Nb and Zr dopants for improved catalysis” published in the issue outlines the work of Keith and his team on improving the performance of tin electrocatalysts for CO₂ reduction.

University of Pittsburgh Chancellor Patrick Gallagher brings up the challenge of climate change and defends the history of our city in a Science article entitled "Pittsburgh myth, Paris reality".

When announcing his decision to withdraw the United States from the Paris Agreement, President Trump reminded the world that, “I was elected to represent the citizens of Pittsburgh, not Paris.” In doing so, he repeated a tired trope: that Pittsburgh is a rusty urban relic—a manufacturing city of steel that has fallen on hard times, held back by unfair global competition and onerous environmental regulation. But such a nostalgic version of Pittsburgh, and of many other communities across the country, is a myth. If the president truly wants to represent the interests of Americans, he would learn from the real histories of these regions and promote economic and environmental progress through research, education, and innovation.

Kevin Chen's article Experimental observation of optical Weyl points and Fermi arc-like surface states, published in Nature Physics, was the subject of a "News and Views" article entitled Topological Photonics: Come to Light. The physics idea leading to this paper originated from Penn State collaborator Mikael Rechtsman.

Topological states of matter can exhibit a range of unique quantum phenomena that are of interest to various fields of classical physics, such as acoustics, mechanics or photonics. Although a number of these topological states have been successfully emulated in photonics, their application has been restricted to certain frequencies. Most topological properties have been demonstrated in two-dimensional (2D) systems; however, a variety of new topological properties have been predicted for three-dimensional (3D) systems. The study published in Nature Physics marks an important step by emulating Weyl points, which constitute the simplest possible topologically nontrivial band structure, in three dimensions.

Subra Suresh will resign as president of Carnegie Mellon University on June 30, making his tenure the shortest in the school’s 117-year history and placing it in uncharted waters as it seeks a new leader for the second time in less than five years.

In a letter Thursday to the CMU community, he wrote, “My wife Mary and I have reflected on the long-term commitment needed to implement the university’s strategic plan, and we feel Carnegie Mellon would be best served now by a president who is ready to make that extended commitment to generating resources and guiding the university toward reaching these objectives.”

Mr. Suresh has been at CMU for four years.