<html><head></head><body>The possibility of achieving room temperature superconductivity took a tiny step forward with a recent discovery by a team of Penn State physicists and materials scientists.The surprising discovery involved layering a two-dimensional material called molybdenum sulfide with another material called molybdenum carbide. Molybdenum carbide is a known superconductor — electrons can flow through the material without any resistance. Even the best of metals, such as silver or copper, lose energy through heat. This loss makes long-distance transmission of electricity more costly.“Superconductivity occurs at very low temperatures, close to absolute zero or 0 Kelvin,” said Mauricio Terrones, corresponding author on a paper in Proceedings of the National Academy of Sciences published this week. “The alpha phase of Moly carbide is superconducting at 4 Kelvin.”When layering metastable phases of molybdenum carbide with molybdenum sulfide, superconductivity occurs at 6 Kelvin, a 50% increase. Although this is not remarkable in itself — other materials have been shown to be superconductive at temperatures as high as 150 Kelvin — it was still an unexpected phenomenon that portends a new method to increase superconductivity at higher temperatures in other superconducting materials.The team used modeling techniques to understand how the effect occurred experimentally.“Calculations using quantum mechanics as implemented within density functional theory assisted in the interpretation of experimental measurements to determine the structure of the buried molybdenum carbide/molybdenum sulfide interfaces," said Susan Sinnott, professor of materials science and engineering and head of the department. "This work is a nice example of the way in which materials synthesis, characterization and modeling can come together to advance the discovery of new material systems with unique properties.”According to Terrones, “It’s a fundamental discovery, but not one anyone believed would work. We are observing a phenomenon that to the best of our knowledge has never been observed before.”The team will continue experimenting with superconductive materials with the goal of someday finding materials combinations that can carry energy through the grid with zero resistance.In addition to Terrones and Sinnott, authors on the PNAS paper, titled “Superconductivity enhancement in phase-engineered molybdenum carbide/sulfide vertical heterostructures,” are doctoral students or graduated doctorate recipients Fu Zhang, Yanfu Lu, Lavish Pabbi, Anna Binion, Tomotaroh Granzier-Nakajima, Tiany Zhang and Zhong Lin; and postdoctoral scholars Kazunori Fujisawa And Yu Lei, Professor Eric Hudson and former Research Assistant Professor Laura Elias, all of Penn State, and Wenkai Zhang and Luis Balcas of Florida State.</body></html>

Layers of molybdenum carbide and molybdenum sulfide allow superconductivity at 50 percent higher temperatures. Image: Elizabeth Flores-Gomez Murray/ Penn State

The possibility of achieving room temperature superconductivity took a tiny step forward with a recent discovery by a team of Penn State physicists and materials scientists.

Room temperature superconductivity creeping toward possibility

materials

Graphene memristors open doors for biomimetic computing. Image: Jennifer M. Mccann/Penn State

As progress in traditional computing slows, new forms of computing are coming to the forefront. At Penn State, a team of engineers is attempting to pioneer a type of computing that mimics the efficiency of the brain’s neural networks while exploiting the brain’s analog nature.

Graphene-based memory resistors show promise for brain-based computing

Schematic of the layout for a lensless camera. Image: Keating/Liu Labs, Penn State

A new type of imaging that does not require a lens and uses reconfigurable particle-based masks to take multiple shots of an object is being developed by researchers at Penn State.

A multishot lensless camera in development could aid disease diagnosis

Artist’s depiction of a phenomenon called stochastic resonance. Researchers studied this technique to apply it to sensors to detect signals too faint to otherwise capture. Image: Bessie Terrones, Penn State MRI

Adding noise to enhance a weak signal is a sensing phenomenon common in the animal world but unusual in manmade sensors. Now Penn State researchers have added a small amount of background noise to enhance very weak signals in a light source too dim to sense.

To make a better sensor, just add noise

An example of a flexible gas sensor worn over a knuckle. Image: Cheng Lab, Penn State

A stretchable, wearable gas sensor for environmental sensing has been developed and tested by researchers at Penn State, Northeastern University and five universities in China.

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