4Hb-TaS₂ is a superconductor that exhibits unique characteristics such as time-reversal symmetry breaking, hidden magnetic memory, and topological edge modes. It is a naturally occurring heterostructure comprising of alternating layers of 1H-TaS₂ and 1T-TaS₂. The former is a well-known superconductor, while the latter is a correlated insulator with a possible non- trivial magnetic ground state. In this study, we use angle resolved photoemission spectroscopy to investigate the normal state electronic structure of this unconventional superconductor. Our findings reveal that the band structure of 4Hb-TaS₂ fundamentally differs from that of its constituent materials. Specifically, we observe a significant charge transfer from the 1T layers to the 1H layers that drives the 1T layers away from half-filling. In addition, we find a substantial reduction in inter-layer coupling in 4Hb-TaS₂ compared to the coupling in 2H-TaS₂ that results in a pronounced spin-valley locking within 4Hb-TaS₂.

4Hb-TaS ₂是一种超导体，具有时间反转对称性破缺、隐藏磁记忆和拓扑边缘模式等独特特性。它是一种天然存在的异质结构，由 1H-TaS ₂和 1T-TaS ₂的交替层组成。前者是众所周知的超导体，而后者是具有可能的非平凡磁基态的相关绝缘体。在这项研究中，我们使用角分辨光电子能谱来研究这种非常规超导体的正常态电子结构。我们的研究结果表明，4Hb-TaS ₂的能带结构与其组成材料的能带结构根本不同。具体来说，我们观察到从 1T 层到 1H 层的显着电荷转移，从而驱动 1T 层远离半填充。此外，我们发现与2H-TaS ₂中的耦合相比，4Hb-TaS ₂中的层间耦合显着减少，这导致4Hb-TaS ₂内明显的自旋谷锁定。