Abstract
The nonlinear-optical response of a material leads to novel phenomena and applications. At present, most nonlinear-optical materials are based on the electric susceptibility. This thesis investigates the magnetic susceptibility as an alternative that might lead to a greatly enhanced nonlinear-optical response. To assess the nonlinearity of test systems, the Schrödinger equation and magnetic dipole moment operator are coded in Python using the finite-difference time-domain (FDTD) method to calculate the eigenstates and eigenenergies of a three-dimensional (3D) toroidal potential well, which is chosen as a prototypical magnetic system. The numerical results compare favorably with the analytical solution of the Schrödinger equation for the special case of a quantum wire, thus validating the method. A calculation of the magnetic dipole moment as a function of magnetic field strength demonstrates a nonlinear magnetic response, suggesting that such materials might be candidates for the next generation of nonlinear-optical materials.