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arXiv · 2007.14316

Temperature dependent diamagnetic-paramagnetic transitions in metal/semiconductor quantum rings

Neal Blackman·Dentcho A. Genov
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Abstract

We present theoretical studies of temperature dependent diamagnetic-paramagnetic transitions in thin quantum rings. Our studies show that the magnetic susceptibility of metal/semiconductor rings can exhibit multiple sign flips at intermediate and high temperatures depending on the number of conduction electrons in the ring ($N$) and whether or not spin effects are included. When the temperature is increased from absolute zero, the susceptibility begins to flip sign above a characteristic temperature that scales inversely with the number of electrons according to $N^{-1}$ or $N^{-1/2}$, depending on the presence of spin effects and the value of $N\,\mathrm{mod}\,4$. Analytical results are derived for the susceptibility in the low and high temperature limits, explicitly showing the spin effects on the ring Curie constant.

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Neal Blackman, Dentcho A. Genov. 2020-11-15. Temperature dependent diamagnetic-paramagnetic transitions in metal/semiconductor quantum rings. https://doi.org/10.1103/physrevb.102.245429

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