Full text loading...
(a) A function generator applies lateral bias to the bicrystal GB and a multimeter (A) measures the transport current. is internally controlled by AFM control unit . (b) Cantilever resonant frequency shift is a quadratic function of and the versus curves taken on the grounded side (엯) and the biased side (∎) show shift in the maximum.
(a) Potential profiles across the GB under bias from and a large electric field of about at the GB under bias (inset). (b) The measured GB potential drop differs very little from the applied bias , when . Above , deviates significantly from , indicating a breakdown of the GB potential barrier.
dependence of current is exponential, which suggests Schottky-type transport mechanism. Four-point curve exhibits the same behavior at low bias but tends to slower growth at high bias.
(a) Nonzero lateral bias induces a spurious topographic step across the GB due to uncompensated electrostatic force. (b) Quantitatively, the step height is proportional to the square of the lateral bias, indicating the tip/surface capacitance can be appropriately modeled as a cone and plane.
Article metrics loading...