Stabilization of Sr-rich ultrathin epitaxial films of La2-xSrxCuO4

Abstract Varying the level of Sr in La 2-x Sr x CuO 4 produces a wide array of electrical properties, spanning metallic, semiconducting, insulating, and superconducting. While the system has been extensively studied, ultrathin films with high Sr content have not been reported. Using oxide molecular beam epitaxy, ultrathin La 2-x Sr x CuO 4 films (0  x x  = 0 to x  = 1.0 causes an initial increase and subsequent decrease in the c-axis lattice parameter and the surface roughness as a function of doping. The films exhibit analogous electrical properties to their bulk and thicker film counterparts. The ability to create ultrathin La 2-x Sr x CuO 4 films at high Sr levels shows promise for inducing unexpected electric properties through dopant modulation effects, such as cation ordering, digital superlattices, and atomically precise interfaces.