High pressure study of charge density wave ordering in BaNi2As2

Recent experiments have revealed the interplay between two charge density wave (CDW) orders and superconductivity in BaNi2As2, a candidate system for charge-driven electronic nematicity. Chemical substitutions have demonstrated the effective tuning of the electronic ground state by chemical pressure and have indicated the unconventional nature of the CDW ordering. Yet, the microscopic origin of the CDWs, their interplay and their association with the underlying nematic instability remain to be clarified. We propose to approach these issues by systematically investigating the effect of hydrostatic pressure (HP) on the crystal structure and the CDW orders of BaNi2As2 using single crystal x-ray diffraction (XRD). Data for the Samples 6,7 and 8.