Tuesday, December 22 at 11 a.m. EST
Abinash Kumar, PhD candidate
Materials Science & Engineering (DMSE)
Relaxor ferroelectrics show slim hysteresis loops, low remanent polarization, high saturation polarization, and exceptional electromechanical coupling, finding applications in ultrasound imaging and energy storage devices. Developing a structure-property relationship in relaxors has been a seemingly intractable problem due to the presence of nanoscale chemical and structural heterogeneities.
In this presentation, Kumar will discuss how researchers employed aberration-corrected scanning transmission electron microscopy (STEM) to quantify the various contributions of nanoscale heterogeneity to relaxor ferroelectric properties in PMN-PT system. Specifically, they found three main contributions—chemical ordering, oxygen octahedral tilting, and oxygen octahedral distortion—that are difficult to otherwise differentiate. Through STEM, the elusive connection between chemical and structural heterogeneity and local polarization variation is revealed. Further, the effects of strain and thickness on PMN-PT thin films will be discussed. Through these measurements, design principles for next generation relaxor material are elucidated.
Attendees can join and participate in the series via Zoom. Meeting ID#: 860 986 455.