Real-Space Characterization of Charge Ordering in Epitaxial La_2-xSr_xCuO₄ films

Injection of charge carriers into the parent Mott insulator gives rise to a plethora of electronic orders in cuprates. Investigation of the behaving and relationship of these exotic orders with high-T_c is of pivotal importance in solving the cuprate conundrum. For this, we present a detailed study of the doping dependent charge orderings in the canonical La_2-xSr_xCuO₄ cuprate thin films. By in-situ STM, we unveil a 4a₀-modulated stripe phase in the vicinity of 0.125 doping, whose commensurability is lost with decreasing Sr concentration. When heavier doped, a grid phase appears whose size is averaged to 4 nm. In the lightly doped regime, on the other hand, a Wigner crystal phase with a distorted-hexagonal patterned electronic structure is captured. Our results contribute to the construction of electronic landscape in the cuprate doping phase diagram, and is of help in illuminating its interplay with superconductivity.