Stark effect on a geometry defined by a cake's slice

By using a variational calculation, we study the effect of an external applied electric field on the ground state of electrons confined in a quantum box with a geometry defined by a slice of a cake. This geometry is a first approximation for a tip of a cantilever of an atomic force microscope. By modeling the tip with the slice, we calculate the electronic ground-state energy as a function of the slice’s diameter, its angular aperture, its thickness and the intensity of the external electric field applied along the slice. For the applied field pointing to the wider part of the slice, a confining electronic effect in the opposite side is clearly observed. This effect is sharper as the angular slice’s aperture is smaller and there is more radial space to manifest itself. q 2005 Elsevier Ltd. All rights reserved.