Electron confinement and correlation in anisotropic quantum dot structures

A number of device concepts based on semiconductor quantum dots have been proposed for use in a variety of quantum information processing applications. Central to these devices is not only single electron confinement and sensitivity, but the ability to discriminate between the singlet and triplet states for indirect measurement of electron spin. In this talk, we will describe theoretical and numerical results for a new device based on InGaAs/InP double quantum well structures whose constraints lead to anistropic quantum dots. We will discuss properties of these quantum dots related to detection and spin readout such as the Coulomb energy and singlet-triplet energy splitting of two-electron states. The quasi-1D nature of these structures leads to qualitatively different results compared to 2D axisymmetric or 3D spherically symmetric dots which have been the canonical cases studied to date. This work was supported by DARPA and the Army Research Office under contract DAA19-01-C-0077.