Journal of Nanomedicine & Nanotechnology

Strain-induced non-volatile domain switching and tunable elastic modulus in freestanding Ba1-xSrxTiO3 membrane by phase-field study

31^st International Conference on Advanced Materials, Nanotechnology and Engineering

April 09-10, 2025 | Webinar

Laveeza Ahmad

Department of Materials Science and Engineering, The University of Texas at Arlington, Arlington, Texas 76019, USA

Scientific Tracks Abstracts: J Nanomed Nanotechnol

Abstract:

Ferroelectrics are key materials in microelectromechanical systems (MEMS), in which the mechanical responses stem from the piezoelectric effect strictly induced by electric fields. Recent advancement of membrane technology offers new opportunities to tune ferroelectric polarizations via strain. However, its influence on the tunability of mechanical responses (such as the effective elastic modulus which is crucial to MEMS) remains underexplored. Here, we developed a phasefield model for free-standing Ba1-xSrxTiO3 membrane with stress-free boundary conditions on top/bottom surfaces, and simulated the non-volatile ferroelectric domain switching driven by the externally applied strain. It is revealed that a tensile/ compressive strain favors in-plane orthorhombic/out-of-plane tetragonal domain structures in BaTiO3, which are stable even after the strain is removed. This results in large difference in elastic modulus of BaTiO3 membrane under different domain states, i.e., a large tunability of elastic modulus. The maximum tunability is achieved at Sr composition (x=0.5), which is close to the ferroelectric-paraelectric phase boundary. At this point, the free energy of the system becomes degenerate, which facilitates ferroelectric-paraelectric phase transition. Our work demonstrates the nature of and elucidates the mechanism of nonvolatile domain switching and tunable mechanical responses in Ba1-xSrxTiO3 membrane, which is key to its potential applications in MEMS systems.

Biography :

Laveeza Ahmad is a Ph.D. candidate in Materials Science and Engineering at the University of Texas at Arlington. Her research focuses on electronic materials, particularly memristors, using computational modeling and nanocomposite thin films. She holds an M.Sc. in Physics from Aligarh Muslim University. Laveeza has co-authored several peer-reviewed publications and has experience as both a research and teaching assistant.