Simulations Reveal Quantum Tunneling Events in Glass

The idea that glass flows like a liquid over long timescales may be a myth, but that doesn’t mean that its atoms are completely frozen. Even at very low temperatures, glasses can shift between similar configurations as a result of quantum tunneling of atoms. Now, Dmytro Khomenko, at Columbia University, and colleagues show by using numerical simulations that the prevalence of such tunneling events depends on the thermal history of the glass. Their findings explain why a glass’s low-temperature properties, like its specific heat, are so sensitive to how the glass was prepared.