Meet our Editors: J. David Musgraves, Juejun Hu & Laurent Calvez
“Glass Science: A field where THE central question still hasn’t been answered”
For millennia humans have prepared and used glass in a variety of applications. But the nature of glass is yet to be fully understood. In this interview, the editors of the Springer Handbook of Glass explain their fascination with this extraordinary material. J. David Musgraves, Chief Scientist at Rochester Precision Optics, Juejun (JJ) Hu, Associate Professor at the Massachusetts Institute of Technology, and Laurent Calvez, Associate Professor at the University of Rennes, pulled together an impressive team of international experts to cover the current state of glass science comprehensively in one book.
In your opinion, which property or behavior of glass makes it the most interesting material?
Juejun Hu (JJ): Glass transition! Glass transition defines glasses as a unique group of materials and distinguishes them from other materials. It is one of the most mysterious phenomena in glass science that has intrigued and baffled many. In fact, in 2005 the Science magazine elected the question “What is the nature of the glassy state?” to be one of the most significant scientific questions yet to be answered.
David Musgraves: I agree with JJ. The glass transition is what we have taken advantage of for centuries in order to form glass into windowpanes, drinking goblets and so forth, but from a scientific standpoint, we still don’t know what exactly it is, or why it happens. It is fascinating to work in a field where THE central question still hasn’t been answered.
In which ways or applications is glass superior to other materials?
Laurent Calvez: Glass combines several properties that - in their combination - make it a superior material: Its transparency is relatively unique. While polymers can be transparent, they suffer from low durability. Glass, on the other hand, is chemically very durable, and in comparison to other materials relatively cheap and yet very formable.
David: It may seem trivial, but think about all of the transparent surfaces that surround you right now! From your contact lenses to your computer screens, to your light bulbs; each of these is either a glass or a plastic - and plastics are just organic glasses, really - the properties of transparency and formability are what caused glass to be used for all of these applications.
JJ: Since my personal background is in optics, for me the answer is clear: glass is the only material that possesses extraordinarily low optical loss and at the same time can be processed into kilometer-long fibers with high throughput. This is why glass fibers can form the backbone of internet that connects all of us today!
What, in your opinion, has been the most significant advancement of the recent years in the field of glass science and why?
Laurent: For me, it is its ability to be easily shaped in its supercooled liquid state. The application in special fibers that allow a broadband supercontinuum is impressive.
JJ: My personal vote goes to the latest developments in the topological constraint theory of glass. Mauro, Yue, and others significantly extended the simple existing theory, which was oversimplified yet elegant. The improved theory has already been applied to guide the design of next-generation glass materials.
David: Haha…. John Mauro and I have a bit of a friendly rivalry going in this area and we just see this picture very differently. But is a perfect example of what makes glass science such fun: it is still a small enough and new enough scientific discipline that you can have these good-natured fights about very fundamental aspects of the field.
What are the biggest challenges for the field still ahead?
David: We only started to understand glass from a scientific standpoint. This means that we’ve potentially only touched the edge of what makes glasses interesting and important. We’ve got a decent handle on how to make window glass, but this is only a very small subset of the full scope of glass science.
JJ: And an improved understanding will help us to engineer new and exciting materials.
Laurent: We mustn’t forget that at a time when resources are getting sparser, the sustainable use and recycling of materials must be a priority. We have the potential to recycle 100% of this material and we should strive to achieve this.
What is the most exciting part of your current research?
Laurent: I built my career working on chalcogenide glass-ceramics for thermal imaging. I am now using my knowledge of glass to focus on tomorrow's applications such as solid batteries, light emitting electrochemical cells…
David: I’m spending a lot of time right thinking about how to make really large - or really small- lenses out of glass, trying to come up with more intelligent ways to make and measure optics from glass.
JJ: If I have to pick one: optical phase change materials and the vast device platforms they enabled. This unique behavior allows us to construct reconfigurable photonic circuits and optical elements that can be re-programmed to adapt to different tasks on-the-fly – this is simply fascinating and has numerous applications.
How would you describe the experience of editing the book?
JJ: I think I speak for all of us if I say that it took a huge amount of time and effort but it was tremendously rewarding. We all learnt so much about different fields of glass science and engineering - and even history and arts! – areas, which otherwise we might not have had the chance to look into. More importantly, we had the opportunity to work with great authors, an excellent team of co-editors and Springer’s editorial team – they all made the experience most enjoyable.
Final question: for whom is this book a “must-read”?
Laurent: This book is meant to be a mine of information for everyone working in the field of glass, a student at the university, a technician or a researcher in academia or industry.
David: We were looking to create a “ one stop shop” for the field of glass science. The discipline is evolving so fast it can be hard to keep track of, but the chapters in the book should give interested readers a jumping off point from which to learn about all aspects of the field.