ABSTRACT
Spin effects, and their possible manipulation by electric gating in quantum dots have received significant attention because of the new physics associated with few spin systems and their potential applications in quantum information processing. This chapter presents a hybrid Local Density Approximation (LSDA)/Diffusion Quantum Monte Carlo (DQMC) method for simulating the electronic configurations of realistic vertical quantum dots. The method computes the three-dimensional self-consistent confining potential from Poisson and Kohn-Sham equations with the realistic device structure comprising hetero-barriers and doping regions with boundary conditions on the electric potential deduced from the external bias applied to the gate. This approach has the unique advantage of combining the flexibility of the LSDA for modeling the device features of the quantum dot with the accuracy of the DQMC for computing the ground state of the many-body system.
