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arXiv · 2002.02877

Anomalous low-energy properties in amorphous solids and the interplay of electric and elastic interactions of tunneling two-level systems

Alexander Churkin·Shlomi Matityahu·Andrii O. Maksymov·Alexander L. Burin·Moshe Schechter
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Abstract

Tunneling two-level systems (TLSs), generic to amorphous solids, dictate the low-temperature properties of amorphous solids and dominate noise and decoherence in quantum nano-devices. The properties of the TLSs are generally described by the phenomenological standard tunneling model. Yet, significant deviations from the predictions of this model found experimentally suggest the need for a more precise model in describing TLSs. Here we show that the temperature dependence of the sound velocity, dielectric constant, specific heat, and thermal conductivity, can be explained using an energy-dependent TLS density of states reduced at low energies due to TLS-TLS interactions. This reduction is determined by the ratio between the strengths of the TLS-TLS interactions and the random potential, which is enhanced in systems with dominant electric dipolar interactions.

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Alexander Churkin, Shlomi Matityahu, Andrii O. Maksymov, Alexander L. Burin, Moshe Schechter. 2021-02-23. Anomalous low-energy properties in amorphous solids and the interplay of electric and elastic interactions of tunneling two-level systems. https://doi.org/10.1103/physrevb.103.054202

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