Spin and Angle-resolved electronic structure investigation in the alternative 1H (Superconducting)-1T(charge density wave) self-staked bulk compound 6R-TaS2

Adjusting interlayer stacking and coupling in van der Waals heterostructures empowers the creation of customizable quantum systems with exotic physics. A fascinating frontier, largely unexplored is the stacking of strongly correlated phases of matter. In this proposal, we intend to study the electronic band structure of 6R-TaS2, a self-stacked bulk vdW material consisting of superconducting 1H TaS2 monolayers interlayered with 1T TaS2 monolayers (a correlated insulator), displaying charge density waves (CDW). This raises the question of how the electronic properties of these two monolayer compounds get modulated when stacked together. First-principal calculations argued that the coexistence of superconductivity and CDW within 6R-TaS2 stems from an amalgamation of the properties of adjacent 1H and 1T monolayers. Interlayer coupling and proximity effect can influence the correlation-driven orbital texture, providing a useful platform for investigating correlation physics in two dimensions. Moreover, a high spin-valley locking in 1H-derived bands is anticipated due to the non-centrosymmetric nature of the 1H layers and a large spin-orbit coupling. Information regarding the parameters of the spin-orbit coupling and the inter-layer coupling strength can be obtained from the degree of spin polarization in the system. This work will employ surface sensitivity of the spin and angle-resolved photoemission spectroscopy technique to observe the system's hidden electronic structure (valley polarization) and its modulation across the phase transition through a comprehensive temperature, photon energy, and light polarization-dependent study.