Professor Kai Sun

Kai Sun of the University of Michigan is a humble physics professor with ambitious goals.

“I’m mainly a paper-and-pencil type of theorist, doing analytical calculations mostly,” Sun said. “My interests are pretty broad, but basically searching for new fundamental principles and new phenomena, especially new phenomena and new physics previously believed to be impossible.”

While his newest study doesn’t quite hit that impossible threshold, it does still update our conception of physical possibilities. A quantum behavior that was thought to be possible only sometimes can actually be readily realized, according to new work from Sun and his colleagues published in the journal Physical Review X.

Taking advantage of this behavior could help manipulate light and other quantum particles in new ways, which could find applications in emerging fields like quantum computing.

The study was funded, in part, by the Office of Naval Research. U-M research fellow Kai Zhang and graduate student Chang Shu also contributed to the work.

Stay weird, quantum mechanics

While classical physics—the set of natural laws governing the majority of what we see and feel in our everyday lives—tends to be black and white, quantum mechanics is famous for being mushier.

For example, in classical physics, waves and particles are different things. But in the ultratiny quantum realm, things like light and electrons act as both waves and particles. In conventional computers, a bit has a value of either zero or one. In quantum computers, quantum bits act as combinations of ones and zeros.

Sun and his colleagues’ new study keeps with quantum’s penchant for finding a blurrier middle ground between either-or binaries.

Please continue reading this article on the U-M Michigan News website.

More Information:
Professor Kai Sun
Research Fellow Kai Zhang
Graduate Student Chang Shu

Study: Algebraic Non-Hermitian Skin Effect and Generalized Fermi Surface Formula in Arbitrary Dimensions (DOI: 10.1103/cwwd-bclc)