论文标题
源自Mott绝缘体框架的新兴准2D金属状态
An emergent quasi-2D metallic state derived from the Mott insulator framework
论文作者
论文摘要
最近对原子单层或几层建筑的明智剥削的近期准2D系统表现出前所未有的物理特性，这些物理特性挑战了对凝结物理学的传统智慧。在这里，我们表明，无限层的srcuo2（SCO）是散装形式的局部丘陵mott绝缘子，当SCO在TIO2端接的SRTIO3（STO）底物上生长时，可以在准2D限制中表现出意外的金属状态。硬X射线芯级光发射光谱显示出明确的费米水平，类似于掺杂金属的孔。软X射线吸收光谱还揭示了类似于掺杂莫特绝缘子的特征。基于这些结果，我们得出结论，在SCO和Sto之间的界面上不会发生孔掺杂。取而代之的是，它来自SCO平板内的链类型和平面类型结构之间的瞬态层。目前的工作揭示了无限层SCO中一种新型的金属状态，并邀请进一步检查以阐明该状态的空间范围。
Recent quasi-2D systems with judicious exploitation of the atomic monolayer or few-layer architecture exhibit unprecedented physical properties that challenge the conventional wisdom on the condensed matter physics. Here we show that the infinite layer SrCuO2 (SCO), a topical cuprate Mott insulator in the bulk form, can manifest an unexpected metallic state in the quasi-2D limit when SCO is grown on TiO2-terminated SrTiO3 (STO) substrates. Hard x-ray core-level photoemission spectra demonstrate a definitive Fermi level that resembles the hole doped metal. Soft x-ray absorption spectroscopy also reveals features analogous to those of a hole doped Mott insulator. Based on these results, we conclude that the hole doping does not occur at the interfaces between SCO and STO; instead, it comes from the transient layers between the chain type and the planar type structures within the SCO slab. The present work reveals a novel metallic state in the infinite layer SCO and invites further examination to elucidate the spatial extent of this state.
