title: What is moving in silica at 1 K? A computer study of the low-temperature anomalies.
abstract: Though the existence of two-level systems (TLS) is widely accepted to explain low-temperature anomalies in many physical observables, knowledge about their properties is very rare. For silica, which is one of the prototype glass-forming systems, we elucidate the properties of the TLS via computer simulations by applying a systematic search algorithm. We get specific information in the configuration space, i.e., about relevant energy scales, the absolute number of TLS, and electric dipole moments. Furthermore, important insight about the real-space realization of the TLS can be obtained. Comparison with experimental observations is included.
authors.affiliation: Westfälische Wilhelms-Universität Münster, Institut für Physikalische Chemie Corrensstrasse 30, 48149 Münster, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Reinisch
authors.forename: A
authors.initials: A
authors.lastname: Heuer