We are entering into the era of nanotechnology and the size of devices is reaching the scale of few nano-meters. A number of new research areas such as nano-photonics, plasmonics and nano-electronics have attracted special attention. It is being projected that these areas will facilitate to tackle the challenges of device miniaturization and high speed data transfer. As long as the size of a device is not very small, in other words there is no need to consider quantum effects; the conventional Maxwell's equations are commonly used. However, when the size of devices reaches a few nano-meters, quantum effects become important and can not be neglected. For quantum analysis, the Schrodinger's equation is commonly evaluated and the solution of this equation provides the quantum characteristics of a system. Therefore, we should use coupled Maxwell's and Schrodinger's equations for devices where both aspects are needed. For simulation many numerical methods have been developed, such as FDTD [1], ADI-FDTD [2] etc. For example, finite difference time domain (FDTD) method is applied to these coupled equations to measure the tunneling current through a potential barrier in [3]. In [4], transmission line matrix approach is used to simulate the coupled equations and is applied to analyze the carbon nano-tube. This coupled approach is also applied to plasmonics structures in [5].