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arXiv · 0809.2847

Exchange interaction and correlations radically change behaviour of a quantum particle in a classically forbidden region

V. V. Flambaum
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Abstract

Exchange interaction strongly influences the long-range behaviour of localised electron orbitals and quantum tunneling amplitudes. It violates the oscillation theorem (creates extra nodes) and produces a power-law decay instead of the usual exponential decrease at large distances. For inner orbitals inside molecules decay is $r^{-2}$, for macroscopic systems $\cos{(k_f r)} r^{-\nu}$, where $k_f$ is the Fermi momentum and $\nu=3$ for 1D, $\nu=$3.5 for 2D and $\nu=$4 for 3D crystal. Correlation corrections do not change these conclusions. Slow decay increases the exchange interaction between localized spins and the under-barrier tunneling amplitude. The under-barrier transmission coefficients in solids (e.g. for point contacts) become temperature-dependent.

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V. V. Flambaum. 2008-09-17. Exchange interaction and correlations radically change behaviour of a quantum particle in a classically forbidden region. https://doi.org/10.1103/physreva.79.042505

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