A Physics Treasure Hidden in the Pattern of Wallpaper

Kane news

An international team of scientists has discovered a new form of insulating material with a metallic surface that could enable more-efficient electronics, or even quantum computing. Their findings were facilitated by the development of a new method for analyzing existing chemical compounds that relies on the mathematical properties that govern the repeating patterns seen in everyday wallpaper.

The research, published in the journal Science, involved a collaboration among groups from the University of Pennsylvania, Princeton University, Sungkyunkwan University, Freie Universität Berlin, and the Max Planck Institute of Microstructure Physics.

The discovery of this phase in crystals of lead-strontium, completes a decade-long search for an elusive three-dimensional material that combines the unique electronic properties of two-dimensional graphene and three-dimensional topological insulators, a phase of matter discovered in 2005 in independent works by Penn physicist Charles Kane and Princeton’s B. Andrei Bernevig.  

“You can think about a topological insulator like a Hershey’s Kiss,” says Kane, a corresponding author on the paper and the Christopher H. Browne Distinguished Professor of Physics. “The chocolate is the insulator, and the foil is a conductor. We’ve been trying to identify new classes of materials in which crystal symmetries protect the conducting surface. What we’ve done here is to identify the simplest kind of topological crystalline insulator.”

Click here to read the full story.

Arts & Sciences News

Azuma and Hart Named Roy F. and Jeannette P. Nichols Professors of American History

Eiichiro Azuma specializes in Asian American and transpacific history, while Emma Hart teaches and researches the history of early North America, the Atlantic World, and early modern Britain between 1500 and 1800.

View Article >
Arts & Sciences Students Honored during 37th Annual Women of Color Day

Sade Taiwo, C’25, and Kyndall Nicholas, a Ph.D. candidate in neuroscience, were honored for their work.

View Article >
Nine College Students and Alums Named Thouron Scholars; Will Pursue Graduate Studies in the U.K.

The Scholars are six seniors and three recent graduates whose majors range from neuroscience to communication.

View Article >
Irma Elo Named Tamsen and Michael Brown Presidential Professor in Sociology

Elo’s main research interests center on inequalities in health and mortality across the life course and demographic estimation of mortality. In recent years, she has extended her research to include predictors of cognition in high-, middle-, and low-income countries.

View Article >
Julia Hartmann Named Fay R. and Eugene L. Langberg Professor in Mathematics

She specializes in algebra and arithmetic geometry, a newer field that applies techniques from algebraic geometry to solve problems in number theory and co-developed the method of field patching.

View Article >
Holger Sieg Named Baird Term Professor of Economics

Sieg focuses his research on public and urban economics, as well as the political economy of state and local governments.

View Article >