SpringerOpen Newsletter

Receive periodic news and updates relating to SpringerOpen.

Open Access NANO EXPRESS

Dimensional Effects on Densities of States and Interactions in Nanostructures

Rainer Dick

Author Affiliations

Physics & Engineering Physics, University of Saskatchewan, 116 Science Place, Saskatoon, SK, S7N 5E2, Canada

Nanoscale Research Letters 2010, 5:1546-1554  doi:10.1007/s11671-010-9675-1

Published: 2 July 2010

Abstract

We consider electrons in the presence of interfaces with different effective electron mass, and electromagnetic fields in the presence of a high-permittivity interface in bulk material. The equations of motion for these dimensionally hybrid systems yield analytic expressions for Green’s functions and electromagnetic potentials that interpolate between the two-dimensional logarithmic potential at short distance, and the three-dimensional r−1 potential at large distance. This also yields results for electron densities of states which interpolate between the well-known two-dimensional and three-dimensional formulas. The transition length scales for interfaces of thickness L are found to be of order Lm/2m* for an interface in which electrons move with effective mass m*, and for a dielectric thin film with permittivity in a bulk of permittivity . We can easily test the merits of the formalism by comparing the calculated electromagnetic potential with the infinite series solutions from image charges. This confirms that the dimensionally hybrid models are excellent approximations for distances rL/2.

Keywords:
Density of states; Coulomb and exchange interactions in nanostructures; Dielectric thin films