Atomic-resolution imaging of the polar (000{1¯}) surface of LiNbO{3} in aqueous solution by frequency modulation atomic force microscopy

Abstract

Atomic resolution images of the polar (000{1¯}) surface of lithium niobate (LiNbO[3]) are achieved by frequency modulation atomic force microscopy operated at the solid-water interface. The measured data reveal a hexagonal surface unit cell. Its lattice constant corresponds to the bulk-truncated structure, suggesting that the high-temperature annealed surface does not reconstruct. Compared to the (000{1¯}) surface, high-resolution imaging on the oppositely charged (0001) surface is considerably more difficult to achieve. This finding is rationalized by density functional calculations that indicate a higher corrugation and softer bonds on the (000{1¯}) surface compared to the (0001) surface.