Time-Domain Simulation of Three Dimensional Quantum Wires

Abstract

A method is presented to calculate the eigenenergies and eigenfunctions of quantum wires. This is a true three-dimensional method based on a direct implementation of the time-dependent Schrödinger equation. It makes no approximations to the Schrödinger equation other than the finite-difference approximation of the space and time derivatives. The accuracy of our method is tested by comparing it to analytical results in a cylindrical wire.

2x4 Hybrid MZI-MMI Configuration with MMI Phase-shifters as a High-speed Optical Switch with Low Power Consumption

“…The transmission characteristics of the MMI coupler can be determined using either the self-imaging theory or numerical methods such as the eigenmode method and beam probe method. This work employed two-dimensional FDTD numerical method instead to optimize and verify the designs of MMIs [32] as it was shown to produce sufficiently accurate results in simulating devices based on SOI channel waveguides. Device design for fabrication purpose was carried out using DW-2000 tool accessed through CMC Microsystems [33].…”

Design of a 2 × 4 Hybrid MMI-MZI Configuration with MMI Phase-shifters

“…Various parameters of the waveguides and heater element are given in Table 2. The top view of the MMI 1 and MMI 4 , and phase shifters MMI 3 and MMI 4 , calculated using MATLAB Mode Solver [18] as well as from FDTD simulation [19], and corresponding waveguide width and access waveguide positions to obtain single self-image at the output port. The device acts as two independent optical switches depending on whether the input is fed through a i1 (A) or a i2 (B)…”

“…Electric field inside the (a) MMI 1 (input through port a i1 ) and (b) MMI 2 (input through port a i2 ). Two-dimensional FDTD numerical method was used to optimize and verify the design [19], as it was shown to produce sufficiently accurate results in simulating devices based on SOI channel waveguides.…”

Hybrid quantum systems for enhanced nonlinear optical susceptibilities

“…[7] The FDTD method benefits from being computationally efficient while being fully generalizable for solving the Schrödinger equation for arbitrary potentials in three dimensions.…”

“…Our theoretical materials discovery program has found that the hyperpolarizability of a cylindrical nanowire with an aspect ratio of at least 10:1, which is attached to a permanent electric dipole with an inert spacer bridge, yields a first hyperpolarizability near the fundamental limit. The ideal configuration is found by varying the dipole strength and distance between the molecule and nanowire while calculating the off-resonant electronic response of an electron using the finite-difference time-domain (FDTD) technique [7]. While many theoretical models yield a hyperpolarizability near the limit, the system proposed here is within reach of modern nano-fabrication techniques.…”