Observation of hidden electronic phases in 1T-TaS₂through conductance fluctuation spectroscopy

Transition metal dichalcogenides have drawn the attention of the research community as they host multiple, competing electronic phases. One of the most studied materials is 1T-TaS₂ which has a multitude of electronically and structurally distinct phases. For example, the collapse of the low-temperature stable commensurate charge density wave (CCDW) phase under various perturbations leads to the appearance of metastable phases is a big puzzle. Using lateral strain as a tuning parameter we probe the effect of varying the interlayer coupling strength on the electronic phases in few-layer 1T-TaS₂. We observe the co-existence of insulating and metallic phases deep within the CCDW phase. Through detailed conductance fluctuation spectroscopy of the electronic ground state, we establish that the mixed-phase consists of insulating regions surrounded by one-dimensional metallic domain walls.  Our study raises the prospect of using 1T-TaS₂ as a prospect for strain-based devices.