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Aharonov-Bohm Effect for Parallel and T-shaped Double Quantum Dots

Yoichi Tanaka·Norio Kawakami
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Abstract

We investigate the Aharonov-Bohm (AB) effect for the double quantum dots in the Kondo regime using the slave-boson mean-field approximation. In contrast to the non-interacting case, where the AB oscillation generally has the period of 4$π$ when the two-subring structure is formed via the interdot tunneling $t_c$, we find that the AB oscillation has the period of 2$π$ in the Kondo regime. Such effects appear for the double quantum dots close to the T-shaped geometry even in the charge-fluctuation regime. These results follow from the fact that the Kondo resonance is always fixed to the Fermi level irrespective of the detailed structure of the bare dot-levels.

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Yoichi Tanaka, Norio Kawakami. 2006-01-19. Aharonov-Bohm Effect for Parallel and T-shaped Double Quantum Dots. https://doi.org/10.1143/jpsj.75.015004

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