Fuhrer A, Lüscher S, Ihn T, Heinzel T, Ensslin K, Wegscheider W, Bichler M
Solid State Physics Laboratory, ETH Zürich, 8093 Zürich, Switzerland.
Nature. 2001 Oct 25;413(6858):822-5. doi: 10.1038/35101552.
Quantum mechanical experiments in ring geometries have long fascinated physicists. Open rings connected to leads, for example, allow the observation of the Aharonov-Bohm effect, one of the best examples of quantum mechanical phase coherence. The phase coherence of electrons travelling through a quantum dot embedded in one arm of an open ring has also been demonstrated. The energy spectra of closed rings have only recently been studied by optical spectroscopy. The prediction that they allow persistent current has been explored in various experiments. Here we report magnetotransport experiments on closed rings in the Coulomb blockade regime. Our experiments show that a microscopic understanding of energy levels, so far limited to few-electron quantum dots, can be extended to a many-electron system. A semiclassical interpretation of our results indicates that electron motion in the rings is governed by regular rather than chaotic motion, an unexplored regime in many-electron quantum dots. This opens a way to experiments where even more complex structures can be investigated at a quantum mechanical level.
环形几何结构中的量子力学实验长期以来一直吸引着物理学家。例如，连接到引线的开口环允许观察阿哈罗诺夫 - 玻姆效应，这是量子力学相位相干的最佳示例之一。电子通过嵌入开口环一侧的量子点时的相位相干性也已得到证明。封闭环的能谱直到最近才通过光谱学进行研究。关于它们允许持续电流的预测已在各种实验中进行了探索。在此，我们报告在库仑阻塞 regime 下对封闭环的磁输运实验。我们的实验表明，迄今为止仅限于少电子量子点的对能级的微观理解可以扩展到多电子系统。对我们结果的半经典解释表明，环中电子的运动由规则而非混沌运动支配，这在多电子量子点中是一个未被探索的 regime。这为在量子力学层面研究甚至更复杂结构的实验开辟了一条道路。
