Glass fashion! Conference staff are easy to spot in these bright shirts. Credit: ACerS
The technical program for the joint DGG-ACerS GOMD meeting began Tuesday morning with five tracks on topics that ranged from industrial-scale melting and furnace design, to emerging applications in energy and biomedicine, to highly theoretical science of the glassy state.
Attendees are taking advantage of the opportunity to work out new collaborations and exchange ideas with a larger glass community. Richard Brow of ACerS GOMD says, “It’s a great meeting. The addition of the DGG gives the GOMD conference a different flavor. There’s a broader audience and deeper discussions in the sessions.”
Each morning and afternoon includes a plenary session for the award lectures, and the first plenary talk was given by Otto Schott Award winner Donald B. Dingwell, professor of earth and environmental sciences from Ludwig-Maximilians-Universität Munich. Specifically, Dingwell is a lab-based vulcanist whose research involves understanding how molten magma acts in the dynamic environment of volcanoes. In other words, he studies naturally-occurring silicate glasses and their massive-scale behaviors. He emphasized the debt his work owed to the silicate glass scientists and the rich literature that he could apply to his work, saying “Thank you, thank you, thank you.”
Dingwell showed how volcanic eruptions vary depending on whether the system passes through the glass transition rapidly or slowly, which depends on factors such as silica content and water content. Several dramatic videos of volcanic eruptions showed slow-moving magma flowing at centimeters per day and fast-moving magma flowing at meters per second rates. Both behaviors can be explained in terms of the glass transition temperature, melt viscosity, porosity, melt fragmentation, and other factors. From a practical perspective, it is important to know which type of flow to expect based on observable data from difficult to access and usually dangerous environments.
The afternoon plenary talk was given by ACerS GOMD Morey award winner Stephen Elliot from Trinity College and University of Cambridge in the United Kingdom. Elliot presented his work on chalcogenide phase change materials, which he described as “the worst of all glass formers—those that crystalize very easily.” The application is random access memory for computers and electronic devices. Presently, two forms of memory exist—nonvolatile, which holds memory without power (example, flash drives); and volatile, dynamic random access memory. DRAM is fast but the computer must remain on. In a “back of the envelope” calculation, Elliot estimated that an attention-grabbing 0.5 exaJ of power could be saved per year if the world’s computers were turned off at the end of the work day.
Elliot is looking for “universal” RAM materials that are nonvolatile but have DRAM performance with switching speeds in the 1 nanosecond regime. Presently there are materials that perform in the 10 nanosecond range, which is useful enough in some circumstances. For example, in late 2012 Nokia introduced PCRAM in its Asha model of cell phones.
“Switching” in PC materials requires cycling very fast between crystallization and amorphization. In order to reach the 1 nanosecond target, Elliot says the amorphous state needs to be even more unstable despite being already very unstable. The breakthrough idea is to separate the nucleation step from the crystal growth step by developing methods of nucleating externally. His group has demonstrated the idea by nucleating with electric pulses. They are also experimenting with magnetic phase change materials.
After an intense day of focusing on technical topics, attendees enjoyed the opportunity to relax at a conference dinner, enjoy some excellent German cuisine, and congratulate student winners of the poster contests (four each from DGG and GOMD). After the meal, the crowd was entertained by an unusual act, which could be described as “gymnastic comedians.” It seemed a bold move on the part of the organizers to choose a comedy act because so often humor is language-dependent and does not translate very well. However, adding in a gymnastic element provided visual comedy as well, and the crowd seemed to enjoy it very much.
The conference continues through Friday midday, with more social activities for students today and more entertainment tonight. If a happy but exhausted colleague shows up in your lab next week, ask whether they have been at the DGG-ACerS GOMD! As for me and Mark Mecklenborg, we head back to the States tomorrow morning. It’s been a great experience, and we appreciate all the effort the DGG and GOMD leaders have put into making this a remarkable event. We look forward to hosting the DGG membership at GOMD in Miami, Florida, next year.