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arXiv 0902.3099cond-mat.mes-hallnlin.CD
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对称性在双量子点中引起巨大的电导峰

Symmetry causes a huge conductance peak in double quantum dots

Robert S. Whitney, P. Marconcini, M. Macucci

摘要:

我们预测了一个巨大的干涉效应,有助于通过大的超净量子点的混沌形状的电导。当双点结构被制成使得点是彼此的镜像时,相长干涉可以使位于对称轴上的隧道势垒有效地透明。我们表明(通过理论分析和数值模拟),这种效果可以是数量级大于众所周知的普遍电导波动和弱本地化(都小于电导量子)。一个小的磁场破坏了这种效应,大大降低了双点电导;这样就得到了一个磁场探测器,它具有与SQUID相似的灵敏度,但不需要超导体。

英文摘要:

We predict a huge interference effect contributing to the conductance through large ultra-clean quantum dots of chaotic shape. When a double-dot structure is made such that the dots are the mirror-image of each other, constructive interference can make a tunnel barrier located on the symmetry axis effectively transparent. We show (via theoretical analysis and numerical simulation) that this effect can be orders of magnitude larger than the well-known universal conductance fluctuations and weak-localization (both less than a conductance quantum). A small magnetic field destroys the effect, massively reducing the double-dot conductance; thus a magnetic field detector is obtained, with a similar sensitivity to a SQUID, but requiring no superconductors.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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