News of MRS Members/Materials Researchers
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researchers to achieve this advancement compared to previous studies. Few materials allow the manipulation of the strain and magnetic states of a multiferroic through direct application of an electric field, because the stable polarization states in most materials are antiparallel and couple similarly to the other order parameters. This is not so for rhombohedral structures, which can switch to one of four energetically equivalent up- or downpolarized states. M. Huijben, Y.H. Chu, and R. Ramesh of the University of California, Berkeley synthesized samples of rhombohedral (100) BFO to take advan-
tage of this. The BFO was deposited atop leads composed of SrRuO3 (SRO) all on a TiO2-terminated (001) SrTiO3 (STO) substrate to promote growth of BFO. The phase field modeling of S. Choudhury and L.Q. Chen of Pennsyl vania State University showed that all four polarization states of BFO can be accessed by the same switching field due to rotationally invariant symmetries in the material and the electric field using phase-field simulations. How then to manipulate the ferroelectric domains? Balke and her co-workers at Oak Ridge, S. Jesse, A.P. Baddorf, and S.V. Kalinin,
found that they could break the symmetry by applying a voltage to a moving PFM tip. They showed that they could repetitively produce domain patterns this way, including a line of closure domains. “This work shows that it is possible to control the switching process to utilize all new possible functionalities,” said Balke, “whether these are local strain sensors, multi-level resistance devices, or information storage devices that write electrically and read magnetically.” JIM RANTSCHLER
News of MRS Members/Materials Researchers William Conyers Herring passed away at his home in Palo Alto, California, on July 23, 2009 at the age of 94. For over five decades he made insightful contributions in both materials science and solid-state physics— W. Conyers Herring a unique example of the value of interdisciplinary research. His theories of capillary phenomena, diffusionlimited plasticity in metals, mechanical behavior of small particles, sintering, and thermionic behavior were recognized in 1980 when he received the Materials Research Society Von Hippel Award with the citation, “Demonstration that whiskers of high crystalline perfection would exhibit extraordinary mechanical properties. He is also held in esteem for his theoretical contributions to the understanding of surfaces and surface tension.” In the same year he received the James Murray Luck Award for Excellence in Scientific Reviewing by the National Academy of Sciences in recognition of his scholarly, comprehensive reviews of thermionic, magnetic, and transport phenomena that are widely cited today. Earlier in 1959 he was awarded the Oliver E. Buckley Award of the American Physical Society for his major contributions to electronic band theory and its applications. When Conyers started school at five years old in the small town of Parsons, Kansas he had already taught himself how to read so well that he wa
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