Abstract
Amorphous solids exhibit quasiuniversal low temperature anomalies whose origin has been ascribed to localized tunneling defects. Using an advanced Monte Carlo procedure, we create in silico glasses spanning from hyperquenched to ultrastable glasses. Using a multidimensional path-finding protocol, we locate tunneling defects with energy splittings smaller than , with the temperature below which quantum effects are relevant ( in most experiments). We find that as the stability of a glass increases, its energy landscape as well as the manner in which it is probed tend to deplete the density of tunneling defects, as observed in recent experiments. We explore the real-space nature of tunneling defects, and find that they are mostly localized to a few atoms, but are occasionally dramatically delocalized.
- Received 22 November 2019
- Accepted 28 April 2020
DOI:https://doi.org/10.1103/PhysRevLett.124.225901
© 2020 American Physical Society
Physics Subject Headings (PhySH)
synopsis
Simulations Reveal Quantum Tunneling Events in Glass
Published 2 June 2020
In a glass, the freedom of atoms to move by quantum tunneling depends on how fast the glass was initially formed.
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