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Materials Science Research Lecture

Wednesday, January 22, 2020
4:00pm to 5:00pm
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Spalding Laboratory 106 (Hartley Memorial Seminar Room)
"Van der Waals Heterostructures from 2D Materials and Beyond"
Xiangfeng Duan, Professor, University of California, Los Angeles,

Abstract:

The heterogeneous integration of dissimilar materials is a long pursuit of material science community and has defined the material foundation for modern electronics and optoelectronics. The typical material integration approaches usually involve strong chemical bonds and aggressive synthetic conditions and are often limited to materials with strict structure match and processing compatibility. Alternatively, van der Waalsintegration, in which freestanding building blocks are physically assembled together through weak van der Waalsinteractions, offers a bond-free material integrationstrategywithout lattice and processing limitations, as exemplified by the recent blossom of 2D van der Waalsheterostructures. Here I will discuss the fundamental forces involved in van der Waalsintegration and generalize this approach for flexible integration of radically different materials to produce artificial heterostructures with minimum interfacial disorder and to enable high-performing devices. Recent highlights include the formation of van der Waalsmetal/semiconductor junctions free of Fermi level pinning to reach the Schottky-Mott limit; the creation of a new class of high-order van der Waalssuperlattices with highly distinct constituents of atomic or molecular layers and tunability; and the development of van der Waalsthin film electronics with unprecedented flexibility and stretchability. I will conclude with a brief perspective on exploring such artificial heterostructures as a versatile material platform with electronic structure by design to unlock new physical limits and enable device concepts beyond the reach of the existing materials.

More about the Speaker:

Dr. Duan received his B.S. Degree from University of Science and Technology of China in 1997, and Ph.D. degree from Harvard University in 2002. He was a Founding Scientist and then Manager of Advanced Technology at Nanosys Inc., a nanotechnology startup founded based partly on his doctoral research. Dr. Duan joined UCLA with a Howard Reiss Career Development Chair in 2008, and was promoted to Associate Professor in 2012 and Full Professor in 2013. Dr. Duan's research interest includes nanoscale materials, devices and their applications in future electronic and energy technologies. Dr. Duan has published over 250 papers with over 55,000 citations, and holds 45 issued US patents. Dr. Duan has received many awards for his pioneering research in nanoscale science and technology, including MIT Technology Review Top-100 Innovator Award, NIH Director's New Innovator Award, NSF Career Award, Alpha Chi Sigma Glen T. Seaborg Award, Herbert Newby McCoy Research Award, US Presidential Early Career Award for Scientists and Engineers (PECASE), ONR Young Investigator Award, DOE Early Career Scientist Award, Human Frontier Science Program Young Investigator Award, Dupont Young Professor, Journal of Materials Chemistry Lectureship, International Union of Materials Research Society and Singapore Materials Research Society Young Researcher Award, the Beilby Medal and Prize, the Nano Korea Award, International Society of Electrochemistry Zhao-Wu Tian Prize for Energy Electrochemistry, and most recently Science China Material Innovation Award and AIP Horizons Lectureship. He is currently an elected Fellow of Royal Society of Chemistry and Fellow of American Association for the Advancement of Science.

For more information, please contact Elizabeth Rodriguez by phone at 626-395-3329 or by email at elizabeth@caltech.edu.