Liao Menghan, Wang Heng, Zhu Yuying, Shang Runan, Rafique Mohsin, Yang Lexian, Zhang Hao, Zhang Ding, Xue Qi-Kun
State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, China.
Beijing Academy of Quantum Information Sciences, Beijing, China.
Nat Commun. 2021 Sep 9;12(1):5342. doi: 10.1038/s41467-021-25671-8.
Superconductivity and charge density wave (CDW) appear in the phase diagram of a variety of materials including the high-T cuprate family and many transition metal dichalcogenides (TMDs). Their interplay may give rise to exotic quantum phenomena. Here, we show that superconducting arrays can spontaneously form in TiSe-a TMD with coexisting superconductivity and CDW-after lithium ion intercalation. We induce a superconducting dome in the phase diagram of LiTiSe by using the ionic solid-state gating technique. Around optimal doping, we observe magnetoresistance oscillations, indicating the emergence of periodically arranged domains. In the same temperature, magnetic field and carrier density regime where the resistance oscillations occur, we observe signatures for the anomalous metal-a state with a resistance plateau across a wide temperature range below the superconducting transition. Our study not only sheds further insight into the mechanism for the periodic electronic structure, but also reveals the interplay between the anomalous metal and superconducting fluctuations.
超导性和电荷密度波(CDW)出现在包括高温铜酸盐家族和许多过渡金属二硫属化物(TMD)在内的多种材料的相图中。它们之间的相互作用可能会引发奇异的量子现象。在此,我们表明,在锂离子插层后,超导阵列能够在同时存在超导性和CDW的TMD——TiSe₂中自发形成。我们通过使用离子固态门控技术在LiTiSe₂的相图中诱导出一个超导穹顶。在最佳掺杂附近,我们观察到磁阻振荡,这表明出现了周期性排列的畴。在发生电阻振荡的相同温度、磁场和载流子密度范围内,我们观察到了反常金属态的特征——在超导转变温度以下的很宽温度范围内存在电阻平台。我们的研究不仅进一步深入了解了周期性电子结构的机制,还揭示了反常金属与超导涨落之间的相互作用。