Braun Center for Submicron Research, Dept. of Condensed Matter physics, Weizmann Institute of Science, Rehovot, 76100, Israel.
Institute of Ecology and Evolution, University of Bern, CH-3012, Bern, Switzerland.
Nat Commun. 2017 Dec 21;8(1):2251. doi: 10.1038/s41467-017-02433-z.
Controlling the transmission of electrical current using a quantum point contact constriction paved a way to a large variety of experiments in mesoscopic physics. The increasing interest in heat transfer in such systems fosters questions about possible manipulations of quantum heat modes that do not carry net charge (neutral modes). Here we study the transmission of upstream neutral modes through a quantum point contact in fractional hole-conjugate quantum Hall states. Employing two different measurement techniques, we were able to render the relative spatial distribution of these chargeless modes with their charged counterparts. In these states, which were found to harbor more than one downstream charge mode, the upstream neutral modes are found to flow with the inner charge mode-as theoretically predicted. These results unveil a universal upstream heat current structure and open the path for more complex engineering of heat flows and cooling mechanisms in quantum nano-electronic devices.
利用量子点接触压缩来控制电流传输，为介观物理的各种实验铺平了道路。人们对这种系统中热传递的日益关注，引发了对可能操纵不携带净电荷（中性模式）的量子热模式的疑问。在这里，我们研究了上游中性模式在分数空穴共轭量子霍尔态中的量子点接触中的传输。采用两种不同的测量技术，我们能够将这些无电荷模式与带电模式的相对空间分布进行比较。在这些状态中，发现有不止一个下游电荷模式，上游中性模式与内部电荷模式一起流动——正如理论预测的那样。这些结果揭示了一种普遍的上游热流结构，并为在量子纳米电子设备中更复杂地设计热流和冷却机制开辟了道路。
