Ramamoorthy Ramesh

Professor Ramesh graduated from the University of California, Berkeley with a Ph. D. in 1987.  He returned to Berkeley in 2004 and is currently the Plato Malozemoff Chair Professor in Materials Science and Physics. Prior to that he was Distinguished University Professor at the University of Maryland College Park. From 1989-1995, at Bellcore, he initiated research in several key areas of oxide electronics, including ferroelectric nonvolatile memories.  His landmark contributions in ferroelectrics came through the recognition that conducting oxide electrodes are the solution to the problem of polarization fatigue, which for 30 years, remained an enigma and unsolved problem. In 1994, in collaboration with S. Jin (Lucent Technologies), he initiated research into manganite thin films and they coined the term, Colossal Magnetoresistive (CMR) Oxides. At Berkeley, he continues to pursue key scientific and technological problems in complex multifunctional oxide thin films, nanostructures and heterostructures. His group demonstrated the existence of a large ferroelectric polarization in multiferroic BiFeO3 films, in agreement with first principle predictions; they also demonstrated electric field control of antiferromagnetism as well as ferromagnetism, a critical step towards the next generation of storage and spintronics devices that are completely electric field controlled. His current research interests include thermoelectric and photovoltaic energy conversion in complex oxide heterostructures. He has published extensively on the synthesis and materials physics of complex oxide materials.  He received the Humboldt Senior Scientist Prize and Fellowship to the American Physical Society (2001). In 2005, he was elected a Fellow of American Association for the Advancement of Science as well as the David Adler Lectureship of the American Physical Society. In 2007, he was awarded the Materials Research Society David Turnbull Lectureship Award and  in 2009, he was elected Fellow of MRS and is the recipient of the 2010 APS McGroddy New Materials Prize.
Plato Malozemoff Chair Professor, Materials Science/ Physics
University of California, Berkeley
 

 

CONTROLLING AND MANIPULATING FERROMAGNETISM WITH AN ELECTRIC FIELD USING MULTIFERROIC OXIDE HETEROSTRUCTURES

Complex perovskite oxides exhibit a rich spectrum of functional responses, including magnetism, ferroelectricity, highly correlated electron behavior, superconductivity, etc.   The basic materials physics of such materials provide the ideal playground for interdisciplinary scientific exploration.  Over the past decade we have been exploring the science of such materials (for example, colossal magnetoresistance, ferroelectricity, etc) in thin film form by creating epitaxial heterostructures and nanostructures.  Among the large number of materials systems, there exists a small set of materials which exhibit multiple order parameters; these are known as multiferroics.  Using our work in the field of ferroelectric and ferromagnetic oxides as the background, we are now exploring such materials, as epitaxial thin films as well as nanostructures.  A particularly interesting problem is that related to electric field control and manipulation of ferromagnetism.  In this talk I will describe to you some aspects of such materials as well as the scientific and technological excitement in this field. Finally I will share my ideas on the most exciting open problems and emerging directions in multiferroics and beyond into the realm of Energy.