Controlling collective electronic states through clean and reversible external stimuli is crucial for realizing functional quantum materials. Here, we report a study on temperature (π) and pressure (π) -tuned charge-density-wave (CDW) orders in the quasi-one-dimensional system of NbSβ’eβ, through single-crystal x-ray diffraction, and electric and magnetotransport measurements. A refined and extended phase diagram is presented, prompting a reevaluation of earlier claims regarding the coexistence of CDW and superconductivity (SC). Here, SC is found to emerge only once all long-range CDWs are suppressed. Notably, the anomalous Hall and magnetoresistance (MR) effects observed at low pressure (LPβΌ0. 8GPa) may arise from distinct carrier types associated with the two competing CDWs, CDW1 and CDW2. These two coexisting CDWs, characterized by distinct modulation vectors, π_π and π_π, show pressure-induced opposing shifts in their π* axis projections (denoted as π^π*β and π^π*β), while preserving a phase-coupling relationship 2 (π_π+π_π) βΌ111. Upon gradual suppression of the long range order CDW2 order, π^π*β of CDW1 stabilizes and enters a decoupled regime within βΌ0. 8β1. 3 GPa, followed by a pronounced change in its periodicity between βΌ1. 3 and 2. 9 GPa. Above 2. 9 GPa, all long-range CDW orders vanish, giving way to emergent superconductivity (SC).
Zhao et al. (Thu,) studied this question.