Scientists at Argonne National Laboratory, Rice University, and Lawrence Berkeley National Laboratory have made significant progress in understanding the mesoscale properties of a ferroelectric material. The material, known as a relaxor ferroelectric, is made up of a complex mixture of lead, magnesium, niobium, and titanium. This material consists of pairs of positive and negative charges that group into clusters called polar nanodomains. When an electric field is applied, these dipoles align in the same direction, causing the material to change shape. Conversely, applying a strain can alter the dipole direction, creating an electric field.
By analyzing the mesoscale properties of the relaxor ferroelectric, scientists have observed that under an electric field, the nanodomains self-assemble into mesoscale structures with dipoles aligning in a complex tile-like pattern. This new form of nanodomain self-assembly was previously unknown and could lead to the design of smaller electromechanical devices. These insights provide a new approach to creating devices that work in ways previously thought to be impossible. The team was able to trace the origin of these structures back to underlying nanoscale atomic motions, highlighting the complexity and intricacy of the material’s behavior.
A fully functional device based on the relaxor ferroelectric was created by Rice University to test the material under operating conditions. This device consists of a thin film of the relaxor ferroelectric sandwiched between nanoscale layers that serve as electrodes to apply a voltage and generate an electric field. Using specialized coherent X-ray nanodiffraction techniques, scientists at Argonne’s Advanced Photon Source were able to map the mesoscale structures within the material. The study revealed strain locations along the borders of the pattern, as well as regions that responded more strongly to the electric field.
The team’s research has implications for the development of energy-efficient microelectronics, such as neuromorphic computing modeled on the human brain. Enhanced X-ray beams made possible by recent upgrades to the Advanced Photon Source will enable further improvements to the device. This technology could help address the increasing power demands of electronic devices worldwide, ranging from cell phones to supercomputers. The research was funded by the DOE Office of Basic Energy Sciences and the National Science Foundation.
The study, published in Science, sheds light on the properties of a material in thin-film form that undergoes shape changes in response to a voltage and vice versa. This breakthrough bridges the nanoscale and microscale understanding of material properties, opening up new possibilities for future technologies. The mesoscale properties of the relaxor ferroelectric were investigated using specialized X-ray techniques, revealing a new form of nanodomain self-assembly that could revolutionize the design of smaller electromechanical devices. This research represents a significant advancement in the field of material science and could lead to the development of more efficient electronic devices.