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arXiv · 1008.1467

Thermal conductance in a spin-boson model: Cotunneling and low temperature properties

Tomi Ruokola·Teemu Ojanen
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Abstract

Bosonic thermal transport through a two-level system is analyzed at temperatures below and comparable to the two-level energy splitting. It is shown that in the low-temperature regime transport is dominated by correlated two-boson processes analogous to electron cotunneling in quantum dots under Coulomb blockade. We present a detailed analysis of the sequential-cotunneling crossover and obtain essentially an analytic description of the transport problem. Perturbative analysis is complemented by employing scaling properties of the Ohmic spin-boson model, allowing us to extract an anomalous low temperature scaling of thermal conductance.

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Tomi Ruokola, Teemu Ojanen. 2010-11-03. Thermal conductance in a spin-boson model: Cotunneling and low temperature properties. https://doi.org/10.1103/physrevb.83.045417

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