Inhomogeneous high temperature melting and decoupling of charge density waves in spin-triplet superconductor UTe2

Periodic spatial modulations of the superfluid density, or pair density waves, have now been widely detected in unconventional superconductors, either as the primary or the secondary states accompanying charge density waves. Understanding how these density waves emerge, or conversely get suppressed by external parameters, provides an important insight into their nature. We use spectroscopic imaging scanning tunneling microscopy to study the evolution of density waves in the heavy fermion spin-triplet superconductor candidate UTe₂ as a function of temperature and magnetic field. We discover that charge modulations, composed of three different wave vectors gradually weaken in a spatially inhomogeneous manner, but persist to a surprisingly high temperature T_CDW ≈ 10-12 K. Interestingly, one of the density wave vectors along the mirror symmetry has a slightly different temperature onset, thus revealing an unexpected decoupling of the three-component CDW state. Importantly, T_CDW determined from our work matches closely to the temperature scale believed to be related to short-range magnetic correlations, providing the first possible connection between density waves observed by surface probes and intrinsic bulk features. Combined with magnetic field sensitivity of the modulations we observe in the non-superconducting state, our work points towards an intimate connection between magnetic correlations and density waves in UTe₂.