5,000 atoms are all you need: The smallest solid-state ferroelectricity

Recent research has broken the size limit of traditional ferroelectric effects, providing experimental evidence and theoretical simulations confirming that structures containing at least 5,000 atoms can still exhibit solid-state ferroelectric effects. can

Published in studies conducted by a joint team from Israel and China. Nature Electronics And Nature Communications under the headings “Ferroelectricity in zero-dimensionality” and “0D van der Waals interfacial sliding ferroelectricity”, respectively.

The ferroelectric effect is a physical phenomenon discovered by Joseph Velasquez in the early 20th century, and it provides an important technological way to store information. Conventional ferroelectric effects are subject to size limitations.

“When the size of conventional ferroelectric materials is small, the significant effect of the depolarization field can cause the original polarization properties to disappear,” explain Professor Gu Yao and Professor Alla Zak. “This size effect limits the use of ferroelectric materials in high-density storage devices.”

Professor Gu Yao from the Beijing Institute of Technology, Professor Alla Zak from the Holon Institute of Technology, and colleagues used tungsten disulfide nanotubes. Interface With about 5,000 Atom at the nanoscale, and observed resistance change and hysteresis phenomena in ferroelectric diodes at interfaces.

Through further experimental and theoretical validation, it was confirmed that the electrical behavior of the ferroelectric diode was due to lattice slip at the interface, enabling the device to produce resistance changes suitable for information storage and approx. Programmable photovoltaic response over the entire visible light wavelength range. . “We are surprised that a 5,000-atom interface system can produce such rich functionality,” the researchers say.

Professor Reshef Teni, from the Weizmann Institute of Science in Israel and co-author of the study, believes that the reduction Ferroelectricity There are significant benefits for future high-density information. Storage. He also believes that this research is of great importance in reducing the size of ferroelectric devices.