Professor David J. Srolovitz, Dean of Faculty of Engineering, The University of Hong Kong
A former Chair Professor at Princeton University, Professor David J. Srolovitz, who took up the position of the Dean of the Faculty of Engineering, The University of Hong Kong (HKU) in 2021, has been amongst the leaders in the growth of material science worldwide for many decades.
It was when considering graduate studies that a family friend advised him to consider materials science. “I was planning to study condensed matter physics when I received that advice. To me, the fields sound the same so I asked what was the difference and he told me ‘materials scientists get more opportunities for career development’ (that was at a point in time when employment in physics was not very easy). This sounds good to me! I never regretted the decision,” he recalled. “People were only then realising that the performance (and limitations) of all engineering systems depend on materials.”
His career began with a strong focus on theoretical and computer modelling. At the time “I could count all of the people in the field on my fingers and toes.” Materials science and computational materials blossomed and have grown into an important field eyed by basic scientists from many disciplines and important industries worldwide.
“Every device, everything people make, is made of materials; materials are the enablers (and limiters) of modern technology,” he explained. From the ancient bronze age to today’s high-tech world heavily dependent on semiconductors such as silicon, materials shape the way people live and interact with the world.
A huge impact on technology
Small changes in materials have a multiplier effect in technology. “An increase in the ability of a jet engine material to perform at a few degrees hotter, means the engine is more efficient, the aeroplane needs to carry less fuel, and the structure of the aeroplane can be lighter. There is a real feedback between materials and technology!” Professor Srolovitz explains.
In his research, Professor Srolovitz studies both the fundamental structure and properties of perfect materials and atomic-scale defects in materials. He points out the old materials science adage “materials are like people, it's their defects that make them interesting.”
Indeed, all materials have defects; most materials' properties are determined by defect properties; a materials scientist manipulates those defects to control material behaviour. Professor Srolovitz’s own work looks at the defects that control the mechanical behaviour of metals and alloys; how they form, how they move, how they interact, how they respond to stress. This work ranges in scale from a few atoms up to billions of atoms. In other projects, he focuses on interfaces between differently oriented crystals and different types of crystals, considering atomic scale details of interface structure, the arrangements of interfaces into microstructures and how those microstructures evolve. Professor Srolovitz is now examining the opto-electronic properties of novel two-dimensional materials. Professor Srolovitz has always been drawn to tackling fundamental problems, fuelled by a strong curiosity, and identifying problems overlooked by many. “I've been fortunate to have made some contributions to topics that nobody looked at seriously before, but became recognised for their importance years later.” Rather than boasting, he was only discussing the serendipitous nature of science. “When I look back, I think I've had the benefit of being in the right place working on the right set of problems interacting with the right set of people at the right time.”
Professor Srolovitz in debate with colleagues in New York
He derives satisfaction from a few chance discoveries which laid the foundation for technological development. When he was teaching at Princeton University, he made a joint discovery with a chair mathematics professor, who, out of interest attended his class on material science, and alerted him to an interesting mathematical problem during a lecture. Together the pair spent a few weeks, often standing together in front of a blackboard, concentrating on solving the problem. “It was a very fundamental problem, one that had been around for 70 years. Some of the greatest mathematicians and physicists worked on it but nobody was able to solve it,” laughed Professor Srolovitz. The pair’s efforts paid off. Their discovery was published in the top journal Nature.
Professor Srolovitz and his colleagues developed several computer simulation methods that later were adopted by researchers worldwide. Doing basic research was also a source of satisfaction to him. “The more applied the problems you work on, the set of technologies you impact tend to be more limited. Applied work can have a big impact but in the narrow area,” he said. “If you think more generally and fundamentally you may not actually be the person responsible for a multi-billion-dollar technology, but that technology rests on some of your ideas. That is very satisfying.”
Professor Srolovitz received a medal for his research contributions
More ground-breaking research ahead
In computer technology, there is a trend to make the basic circuit elements smaller and smaller, leading to more and more elements on a single microchip. This paved the way for dramatic increases in circuit complexity and computer processing power.
As highlighted by Moore's law, the total number of transistors on a microchip doubles every two years; this “law” was valid for decades as circuits kept increasing annually over the past few decades. While transistor sizes used to be measured in millimetres, they are now measured in nanometers (a million times smaller); this allows scientists to pack billions of transistors and achieve nearly 100 gigabytes of memory on a single microchip.
But Professor Srolovitz notes that this trend cannot continue forever – eventually the required dimensions are smaller than atoms. This is where new materials come in. “A hot research area right now is two-dimensional (sheet-like) materials. Graphene was a classic example. But the palatte of new two-dimensional materials is exploding. These atomically thick materials not only pack together efficiently, but also exhibit a wide range of new properties.” He concludes, “the next and next, next generation of micro-electronics is very exciting.”
Professor Srolovitz (middle) was appointed as an elected member of the US National Academy of Engineering
Pivotal cross-disciplinary research
Having produced more than 500 research articles over the past 40 years, Professor Srolovitz notes the rising importance of interdisciplinary, collaborative research. “What makes a good material, in a technological sense, is not simply the basic properties of the material but whether you're able to actually achieve those properties in a practical and cost-effective manner at a technologically relevant scale.” To address this, most engineering today occurs in teams with specialists from different fields. “No field of engineering is an island, every piece of engineering touches other parts, as well as science and mathematics, of course, but also, increasingly artificial intelligence. At HKU, I see this type of interconnectedness in every department,” said Professor Srolovitz, who is also Professor of Mechanical Engineering and Chair of Materials Theory at HKU.
“Consider medicine and biomedical engineering; there is a tremendous need to understand large amounts of data and to organise it efficiently; these things are what engineers are trained for. In fact, many (perhaps most) major advances in medicine are at some level tied to advances in devices and the data they produce. DNA sequencing, diagnostics equipment, x-ray systems, magnetic resonance imaging - all of these elements of modern medicine are ultimately tied to engineering and data problems.”
Even humanities and the arts are impacted by data science and computer science today, as exemplified by the growing field of digital humanities. “Many computer scientists have won Oscars for their algorithm on major animated films; some have won multiple Oscars,” Professor Srolovitz reflects.
Moving to Asia
In 2004, Professor Srolovitz was Chairman of the Department of Mechanical and Aerospace Engineering at Princeton University. He moved to Singapore to run a research institute in 2009 before returning to the University of Pennsylvania in 2012 to lead the Penn Institute for Computational Science.
Professor Srolovitz was discussing a research problem with scientists in Singapore
He returned to Asia in 2018, after being invited by some former students to start a new materials science department at the City University of Hong Kong. He moved to HKU as Dean of Engineering in 2021. He revels in HKU’s intellectual atmosphere which he attributes to the University’s long years of tradition, the diversity of its academic environment and faculty and student devotion to research. “HKU is the only university that ‘feels’ like a real university to me. It is the eclectic mixture of classical and modern buildings on campus and the traditions of academic excellence,” he said.
He looks forward to continued exciting developments within the Faculty of Engineering, which as he said, has been successful in stepping up its collaborative research and opening up to opportunities from diverse disciplines. “Some faculty members feel like they could just as easily be in other departments, in terms of what they do and who they work with. There is a spirit of excitement as we embrace new directions.”
On the education side, the undergraduate training provided by the Faculty equips students with basic skills, hands-on opportunities and instills a love for engineering, making them the most employable in Hong Kong. “Since engineering is about turning ideas into reality, to create new things, to enable the future – engineering is an exciting place to be!”
Hong Kong’s Unique Position
A fellow of the Hong Kong Academy of Engineering Sciences, Professor Srolovitz is optimistic about the development of science and technology in Hong Kong, and the resulting bright prospects for relevant graduates.
HKU Engineering, under his leadership, has had great success in recruiting professors from top universities around the world; that is also due to HKU’s tradition of academic excellence and Hong Kong’s unique position in China with its long tradition of being connected with the international community.
HKU Engineering plays an important role in the region and the country based on Hong Kong’s international position, HKU’s international style in research and development environment and because of the clear direction from the Central and the HKSAR governments to foster innovation and technology. “There is a lot of investment in academic research and technological industry today. We are at a special point in time and space; it’s a great time to be an HKU Engineer.”
Professor Srolovitz gave opening remarks in the Asian Engineering Deans’ Summit 2023