Our group utilizes different forms of numerical modeling, from Finite difference time domain (FDTD), monte carlo particle simulations (SIMION), particle in a cell (PIC) and a home made Vlasov solver in order to solve problems in both microscopy development and Fusion research. Utilizing a 3D Finite Difference Time Domain (FDTD) technique for the modeling of tip shapes coupled with the use of a dual-beam Focused Ion Beam (FIB), it has been possible to design tips with high electric field enhancement factors in order to achieve ultra-high resolution spectroscopic images. We use our universities high performance clusters (HPCs) to solve these complex problems.
Finite Difference Time Domain (FDTD)
Finite Difference Time Domain (FDTD) is a time domain numerical modeling technique which can be successfully applied to nanoscale field calculations. Proper material parameters are applied in order to determine the correct field distribution of small objects in small time scales. FDTD is used in our group for modeling tip field enhancement and in the near-field and surface plasmon resonance for thin films and nanoparticles.
GUI of one of the commercial packages we use in order to calculate field distributions. This program utilizes a proprietary material parameterization, which gets very accurate material descriptions.Vlasov Equation
The Vlasov equation describes the time evolution in phase space of a collisionless plasma. Here, a numerical Vlasov solver was used to model a discharge in a spherically convergent fusion device; several snapshots of the ion phase space distribution are shown.