Unique phenomena because of the interaction of various quantum orders have been noticed and the examine of those phenomena has emerged as a brand new frontier in condensed matter analysis, particularly within the two-dimensional restrict. Right here, we report coexistence of cost density wave (CDW), superconductivity, and nontrivial topology in monolayer 1H-MSe2 (M = Nb, Ta) triggered by momentum-dependent electron-phonon coupling via electron doping. At a vital electron doping focus, new 2×2 CDW phases emerge with nontrivial topology, Dirac cones, and van Hove singularities. Curiously, these 2×2 CDW phases are additionally superconducting. Our findings not solely reveal a route in direction of realizing nontrivial digital characters by CDW engineering, but in addition present an thrilling platform to modulate totally different quantum states on the confluence of CDW, superconductivity, nontrivial topology, and electron-phonon coupling.
