A research team, led by Professor Junhee Lee from the Graduate School of Semiconductor Materials and Devices Engineering at UNIST, has demonstrated through quantum mechanical calculations that charged domain walls in ferroelectrics—once thought to be unstable—can, in fact, be more stable than the bulk regions.

This discovery opens new avenues for developing high-density semiconductor memory devices capable of storing information as binary states (0s and 1s) based on the presence or absence of domain walls.

This research was conducted in collaboration with researchers Pawan Kumar and Dipti Gupta, who served as the first author and co-author, respectively. The research is published in the journal Physical Review Letters.

One of the most profound open questions in modern physics is: “Is gravity quantum?” The other fundamental forces—electromagnetic, weak, and strong—have all been successfully described, but no complete and consistent quantum theory of gravity yet exists.

“Theoretical physicists have proposed many possible scenarios, from gravity being inherently classical to fully quantum, but the debate remains unresolved because we’ve never had a clear way to test gravity’s quantum nature in the lab,” says Dongchel Shin, a Ph.D. candidate in the MIT Department of Mechanical Engineering (MechE).

“The key to answering this lies in preparing mechanical systems that are massive enough to feel gravity, yet quiet enough—quantum enough—to reveal how gravity interacts with them.”