Entanglement Properties of the Two-Electron Quasi-One Dimensional Gaussian Quantum Dot

We analyze the entanglement characteristics of the quasi one-dimensional quantum dot containing two Coulombically interacting electrons in an inverted Gaussian potential. The linear entropy of the lowest energy states is calculated in the whole range of the effective interaction strength g for different parameters of the longitudinal potential and the lateral radius of the quantum dot. We employ the configuration interaction method with complex-coordinate rotation, since the considered states become autoionizing resonances at the interaction strength above the critical value g(th). We study the dependence of the linear entropy on the parameters of the quantum dot and discuss how the stability properties of the system are characterized by the entanglement between the electrons.