Research seminar "Twists and turns in road to materials discovery:
tuning local structural order in functional oxides".

Description

Functional oxides enable multiphysical coupling within compact solid-state devices and are therefore critical for many modern technologies. Among functional oxides, ferroelectric and antiferroelectric ceramics are vitally important for applications, such as electromechanical actuators, load and heat sensors, telecommunications, electronics, solid-state cooling and energy harvesting, due to their attractive electrical, electromechanical and electrothermal properties. The fast pace of technological advancements have led to a surge in the research and development of new (anti)ferroelectric materials, which are expected to provide not only large functional properties, but also satisfy requirements for more extreme operational conditions and stricter environmental regulations. Due to such diverse demands, many of the empirically developed ferroelectric compositions tend to be highly complex, with resultant microscopic disorder that are nevertheless poorly understood. Therefore, the path to rational engineering of new (anti)ferroelectrics lies within the ability to understand and ultimately control inherent structural disorders over different length scales – from atomic to microscopic and beyond. This requires characterization of not only the long-range periodic crystallographic structure of a material but also the nature and relative arrangements of the aperiodic local structural units. In this talk, I will present results from our recent X-ray and neutron scattering experiments, which reveal the unexpected ways in which macroscopic properties in complex oxide ferroelectrics emerge from tuning of local structural order, and opportunities therein for the design of new materials with better properties. Finally, I will discuss the exciting prospect of leveraging knowledge of local structural order towards the design of 3-D printed architected ferroelectrics.

Practical information

• 20 April at 1.45pm
• At Amphi I, Eiffel building, CentraleSupelec
• Seminar online also: Link to connect to the seminar

Short Bio

Abhijit Pramanick is an Assistant Professor at the City University of Hong Kong. Since January 2023, he is also a Senior Jean D’Alembert Fellow at the University Paris Saclay.
He obtained his Bachelor in Engineering from the National Institute of Technology, India, and his Master in Engineering from the Indian Institute of Science, Bangalore. He received his Ph.D. in Materials Science and Engineering in 2009 from the University of Florida, Gainesville.
After his Ph.D., he held a postdoctoral appointment at the Alfred University in New York, USA. Subsequently, he moved to the Oak Ridge National Laboratory, where he spent three and half years working on the applications of different X-ray and neutron scattering techniques to understand the microscopic origins of functional responses in ferroelectric and ferromagnetic materials.
He has coauthored more than 55 publications. For his work on in situ structural characterization of ferroelectric ceramics using X-ray diffraction, he was awarded the prestigious Edward C. Henry Award by the American Ceramic Society in the years 2010 and 2012.
His current research group at City University of Hong Kong focuses on the design, synthesis and multiscale structure−property characterization of functional oxides, with an emphasis on ferroelectrics and antiferroelectric ceramics, which are useful for high−power energy storage, electromechanical sensors/actuators, energy harvesting and solid−state cooling.

References

• C. S. Htet, S. Nayak, A. Manjon-Sanz, J. Liu, J. Kong, D. R. Sorensen, F. P. Marlton, M. R. V. Jorgensen, A. Pramanick*, Atomic structural mechanism for ferroelectric-antiferroelectric transformation in perovskite NaNbO3, Physical Review B 105, 174113 (2022)

• J. Kong, J. Liu, F. Marlton, M. R. V. Jorgensen, A. Pramanick,* “Local structural mechanism for phase transition and ferroelectric polarization in the mixed oxide K0.5N0.5NbO3”, Physical Review B, 103, 184104 (2021)

• S. Venkateshwarlu, L. K. Venkataraman, V. Segouin, F. P. Marlton, H. C. Hin, D. Chernyshov, Y. Ren, M. R. V. Jorgensen, S. Nayak, J. Rodel, L. Daniel, A. Pramanick,* “Large electromechanical strain and unconventional domain switching near phase convergence in a Pb-free ferroelectric”, Communications Physics, 3, 193 (2020).

• F. P. Marlton, S. Nayak, S. Venkateshwarlu, N. H. Chan, J. Kong, Y. Zhang, M. Tucker, M. R. V. Jorgensen,* A. Pramanick,* Broad distribution of local polar states generates large electrothermal properties in Pb-free relaxor ferroelectrics, Chemistry of Materials, 33, 8844 (2021)

• A. Pramanick,* W. Dmowski, T. Egami, A. Setiadi Budisuharto, F. Weyland, N. Novak, A. Christianson, J. M. Borreguero Calvo, D. L. Abernathy, M. R. V. Jorgensen, “Stabilization of polar nanoregions in Pb-free ferroelectrics”, Physical Review Letters 120, 207603 (2018)