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arXiv · 1912.01535

Stable and Metastable Kinetic Ferromagnetism on a Ring

Ilya Ivantsov·Hernan B. Xavier·Alvaro Ferraz·Evgenii Kochetov
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Abstract

Performing an exact diagonalization of the effective spin problem, a ferromagnetic ground state of kinetic origin is shown to emerge in a system of $N$ strongly correlated electrons on a $L$-site ring ($L > N$). This phenomenon is brought about by the quantum necklace statistics originated from the no double occupancy constraint leading to a fractional shifted electron momentum quantization. As a consequence of such special energy level distribution, the kinetic ferromagnetism is stable only for $N=3$. For odd $N>3$ the fully polarized FM state energy is only a local minimum but it is protected by a finite energy barrier that inhibits one spin-flip processes. The metastable ferromagnetic state survives perturbations of small magnitude opening up a possibility of being experimentally observed by an appropriate tuning of the interdot tunneling amplitudes in currently available quantum dot arrays.

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Ilya Ivantsov, Hernan B. Xavier, Alvaro Ferraz, Evgenii Kochetov. 2019-12-03. Stable and Metastable Kinetic Ferromagnetism on a Ring. https://doi.org/10.1103/physrevb.101.195107

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