Physical Sciences & Mathematics

Dr Marcus Noack and Dr Mark Risser, researchers at Lawrence Berkeley National Laboratory, have recently proposed a significant advancement in the area of machine learning and data science that promises significant computational improvements: the enhancement of exact Gaussian Processes for large datasets, significantly improving data analysis capabilities for samples even beyond 5 million data points.

The Principle of Least Action is a well-known tool for mathematicians and theoretical physicists. Simply put, the Principle of Least action states that, for a system to progress from one state to another, the variation in the average kinetic energy of the system minus the average potential energy of the system will be as little as possible. Dr Ivan Kennedy from the University of Sydney has found that the application of this important theorem, combined with the idea of a pervasive quantum field, to processes such as chemical reactions, atmospheric phenomena, and stellar structure, yields some unexpected but exciting results.

One of the most fundamental chemical phenomena in existence is that of the carbon-carbon bond. It gives carbon atoms the ability to form the backbone of all organic chemistries; without it, life itself could not exist. Therefore, understanding how to make, break and manipulate this crucial bond is the secret to unlocking endless potential options for chemical synthesis. Professor Jeremy May and his team at the University of Houston, USA, have been developing methods to control the formation of these bonds, significantly furthering the field of organic synthesis.

Superconducting quantum computers offer exciting potential for the future but are currently limited by their low operating temperature. Professor John Miller and his team at the University of Houston have been working on these problems, looking at how we can operate superconducting quantum systems at higher temperatures and considering the properties of charge density wave materials. He also highlights the applications of this work in quantum information processing.

Our understanding of physics changed dramatically in the 20th century, with the advent of the Standard Model of Particle Physics, which builds on quantum mechanics and Einstein’s theory of relativity – two of the most successful theories in the history of science. However, we know that our theories are incomplete, but finding out what’s beyond the Standard Model is difficult because it’s such a successful theory. Professor Alison Lister and her colleagues at the University of British Columbia and around the world are poking holes in the Standard Model, towards finding a new theory that gives a more complete description of the universe.

Metallic glasses are extraordinary materials that can be formed by rapidly cooling certain mixtures of molten metals. Their unique properties make them extremely desirable for various technological applications. However, scientists do not fully understand the processes that drive the formation of metallic glasses, and as such, they remain difficult to design and optimise for specific purposes. Dr Nicholas Mauro and his team at St. Norbert College in Wisconsin have been researching metallic glasses to understand exactly how these materials form from various molten alloys. By understanding the mechanisms that lead to the formation of metallic glasses, the team’s work aids in the design of new metallic glasses and enables their optimisation for specific technological applications.

The ability to generate stable and reproducible plasma is central to many aspects of research and technology. Through his research, Professor Michel Moisan and his team at Université de Montréal (UdeM) explored the capabilities of various devices they patented that produce plasma columns simply and efficiently, using radiofrequency or microwaves. Applications of these devices range from the sterilisation of medical equipment, to purifying noble gases such as xenon for ion-thrusters that ensure the repositioning of communication satellites.

A combination of dwindling oil reserves and increasing pollution means that the plastic industry must be urgently transformed before it’s too late. The efforts of researchers, including Dr Jinwen Zhang and his colleagues at Washington State University, mean that solutions are becoming increasingly available. Through the development of malleable and self-healable plastics, created from both existing petrochemical and renewable chemical feedstocks, Dr Zhang’s team is creating stronger, more resilient plastics that can be easily recycled.

Despite the numerous opportunities presented by quantum computers, their practical use has so far been hindered by their vulnerability to the surrounding environments. Dr Badih Assaf, Dr Xinyu Liu and their colleagues at the University of Notre Dame, Indiana, show how these problems could be overcome, through the use of an exotic class of hybridised materials named ‘topological superconductors’. Through the optimised fabrication of these materials, and a detailed analysis of their quantum properties, the team’s results could pave the way for the widespread use of topological superconductors in robust and practical quantum computers.

Modern microelectronics is currently facing a profound challenge. The demand for even smaller and more closely packed electronics has hit a stumbling block: the power emitted in these devices releases more heat than can be efficiently removed. Now, Professors Valerii Vinokur, Anna Razumnaya, and Igor Lukyanchuk propose a solution based on the seemingly counterintuitive phenomenon of ‘negative capacitance’. The effect is surprisingly linked to an intriguing topological structure, which is found time and again across a broad range of scientific fields.

Quasicrystals are among the newest and most exciting discoveries in the wider field of materials physics – but to date, many aspects of their exotic physical properties remain entirely unexplored. Since soon after their initial discovery, Dr Zbigniew Stadnik at the University of Ottawa has made important contributions to our understanding of quasicrystals, including their magnetic and electronic characteristics. Building on his decades of experience in the field, he now hopes to gain a complete understanding of the fundamental properties of these materials – potentially opening up a broad new range of real-world applications.

As fundamental components of our electronic and optical devices, semiconductors are essential to our modern way of life. Dr Yasuo Koide of the National Institute for Material Science in Japan has an extensive history of researching and developing these unique materials. Alongside his colleagues, Dr Koide continues to break through the boundaries of our existing knowledge to create new and exciting technologies.

The ability to produce high-quality beams of fast-moving electrons is crucial, both to everyday technologies and scientific experiments. Today, there is a growing need for electron sources that can better meet the stringent demands of these applications. Michigan State University graduate student Mitchell Schneider, together with colleagues at Argonne National Laboratory and Los Alamos National Laboratory, has now made significant strides towards meeting these demands. Drawing from the latest advances in materials science, nanotechnology, and computational modelling, his team has now demonstrated some of the most advanced electron sources ever developed.

The process of inventing new and exciting technologies often begins with the development of unique and novel materials. The road to creating a new material has many stages, ranging from how we acquire the raw components, to how they are processed, and how they are ultimately used. Dr Mauricio Morel Escobar and his team at the Universidad de Atacama, Chile, have been investigating the synthesis, properties and optimisation of materials, towards the development of clean, energy-efficient technologies and manufacturing methods. They are also working to address the energy crisis, by exploring how materials can be used to store sustainable fuels.