arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2103.11989cond-mat.mes-hallcond-mat.str-el
收藏

范德华异质结构中的人工重费米子

Artificial heavy fermions in a van der Waals heterostructure

Viliam Vaňo, Mohammad Amini, Somesh Chandra Ganguli, Guangze Chen, Jose L. Lado, Shawulienu Kezilebieke, Peter Liljeroth

摘要:

重费米子系统代表了一种典型的强关联态物质。它们已被用作研究奇异行为的平台,从量子临界性和非费米液体行为到非常规拓扑超导性。重费米子产生于局域磁矩和传导电子之间的交换相互作用,这导致了众所周知的近藤效应。在近藤晶格中,局域矩之间的相互作用产生了具有重有效质量的带。到目前为止,这种有趣的现象只在含有4f或5 f电子的稀土元素的化合物中实现。在这里,我们实现了一个设计师范德华异质结构,人工重费米子出现从近藤耦合之间的晶格局域磁矩和巡回电子在1 T/1H-TaS $_2$异质结构。我们研究的异质结构,使用扫描隧道显微镜(STM)和光谱(STS),并表明,根据单层的堆叠顺序,我们可以揭示本地化的磁矩和相关的近藤效应,或导电电子与重费米子杂交间隙。我们的实验实现了一个最终可调的平台,为未来的实验探索增强多体相关性,量子临界性的维度调整,以及二维人工重费米子系统中的非常规超导性。

英文摘要:

Heavy fermion systems represent one of the paradigmatic strongly correlated states of matter. They have been used as a platform for investigating exotic behavior ranging from quantum criticality and non-Fermi liquid behavior to unconventional topological superconductivity. Heavy fermions arise from the exchange interaction between localized magnetic moments and conduction electrons that leads to the well-known Kondo effect. In a Kondo lattice, the interaction between the localized moments gives rise to a band with heavy effective mass. This intriguing phenomenology has so far only been realized in compounds containing rare-earth elements with 4f or 5f electrons. Here, we realize a designer van der Waals heterostructure where artificial heavy fermions emerge from the Kondo coupling between a lattice of localized magnetic moments and itinerant electrons in a 1T/1H-TaS$_2$ heterostructure. We study the heterostructure using scanning tunneling microscopy (STM) and spectroscopy (STS) and show that depending on the stacking order of the monolayers, we can either reveal the localized magnetic moments and the associated Kondo effect, or the conduction electrons with a heavy-fermion hybridization gap. Our experiments realize an ultimately tuneable platform for future experiments probing enhanced many-body correlations, dimensional tuning of quantum criticality, and unconventional superconductivity in two-dimensional artificial heavy-fermion systems.

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。

↑