Xia Yipu, Zhang Junqiu, Jin Yuanjun, Ho Wingkin, Xu Hu, Xie Maohai
Physics Department, The University of Hong Kong, Pokfulam Road, Hong Kong.
Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
ACS Nano. 2020 Aug 25;14(8):10716-10722. doi: 10.1021/acsnano.0c05397. Epub 2020 Aug 10.
A mirror twin-domain boundary (MTB) in monolayer MoSe represents a (quasi) one-dimensional metallic system. Its electronic properties, particularly the low-energy excitations in the so-called 4|4P-type MTB, have drawn considerable research attention. Reports of quantum well states, charge density waves, and the Tomonaga-Luttinger liquid (TLL) have all been made. Here, by controlling the lengths of the MTBs and employing different substrates, we reveal by low-temperature scanning tunneling microscopy/spectroscopy, Friedel oscillations and quantum confinement effects causing the charge density modulations along the defect. The results are inconsistent with charge density waves. Interestingly, for graphene-supported samples, TLL in the MTBs is suggested, whereas that grown on gold, an ordinary Fermi liquid, is indicated.
单层MoSe中的镜像双畴边界（MTB）代表一个（准）一维金属系统。其电子特性，特别是所谓4|4P型MTB中的低能激发，已引起了相当多的研究关注。关于量子阱态、电荷密度波和汤川-卢廷格液体（TLL）的报道均已出现。在此，通过控制MTB的长度并采用不同的衬底，我们利用低温扫描隧道显微镜/光谱揭示了弗里德尔振荡和量子限制效应，这些效应导致了沿缺陷的电荷密度调制。结果与电荷密度波不一致。有趣的是，对于石墨烯支撑的样品，表明MTB中存在TLL，而对于生长在金（一种普通费米液体）上的样品，则显示为普通费米液体。
