Quantum weirdness

April 14, 2020
This article appeared in Berkeley Engineer magazine, Spring 2020

Upending a basic tenet of classical physics, a study by Berkeley researchers has shown that heat energy, in the form of molecular vibrations, can travel across a few hundred nanometers of a complete vacuum, thanks to a quantum mechanical phenomenon called the Casimir interaction. The discovery, led by mechanical engineering professor Xiang Zhang, could have profound implications for the design of computer chips and other nanoscale electronic components where heat dissipation is key.

“Heat is usually conducted in a solid through the vibrations of atoms or molecules, or so-called phonons — but in a vacuum, there is no physical medium. So, for many years, textbooks told us that phonons cannot travel through a vacuum,” said Zhang. “What we discovered, surprisingly, is that phonons can indeed be transferred across a vacuum by invisible quantum fluctuations