Electronic structure of the BaTi 2 As 2 O parent compound of the titanium-based oxypnictide superconductor

作者：Haichao Xu, Min Xu, Rui Peng, Yiting Zhang, Q. Q. Ge, Feiyu Qin, Mingxu Xia, Jianjun Ying, X. H. Chen, Xiang‐Long Yu, Liang‐Jian Zou, Masashi Arita, K. Shimada, M. Taniguchi, Dong-Hui Lu, Bin Xie, D. L. Feng · 发表于：Physical Review B · 年份：2014 · DOI：10.1103/physrevb.89.155108 · 被引用次数：18 · 研究领域：Iron-based superconductors research、Rare-earth and actinide compounds、Physics of Superconductivity and Magnetism

The electronic structure of ${\text{BaTi}}_{2}$${\text{As}}_{2}O$, a parent compound of the newly discovered titanium-based oxypnictide superconductors, is studied by angle-resolved photoemission spectroscopy and first-principles calculation. The experimental electronic structure shows a multiorbital nature and three-dimensional character, which is consistent with the calculated results. An anomalous temperature-dependent spectral weight redistribution and broad line shape indicate the incoherent nature of the spectral function. At the density-wave-like transition temperature around 200 K, a partial gap opens at the Fermi patches. These findings suggest that ${\text{BaTi}}_{2}$${\text{As}}_{2}O$ is likely a charge density wave material in the strong-interaction regime.