Posted on Thu 19 April 2018 in plasmonics • Tagged with plasmonics, python
I use differential evolution method to fit the dielectric functions of metals using Differential Evolution method.
Posted on Sat 13 June 2015 in Plasmonics • Tagged with electromagnetism, FDTD, MEEP, octave, Plasmonics
Here is how I was implementing plasmonic materials in meep 1.1. Unlike Meep 1.1, Meep >= 1. 2 changed the way materials are defined.
Here I will describe how to change the material definition code from meep1.1 to meep 1.2 . Please note that one can still use …
Posted on Tue 22 January 2013 in Plasmonics • Tagged with electromagnetism, FDTD, MEEP, Plasmonics
This article is about simulating localized plasmon resonances in metal nanospheres using MEEP package. Generally, I am interested in solving three problems in LSPR systems:
Calculate the extinction, scattering, absorption spectra of metal nanoparticle
The procedure for doing this is very similar to the method I mentioned here.
Calculating the …
Posted on Wed 07 December 2011 in Plasmonics • Tagged with electromagnetism, octave, Plasmonics
[latexpage]
A thin metal film in dielectric (also known as dielectric-metal-dielectric configuration) can support surface plasmons that are different in nature to the ones observed in thick metal-dielectric interfaces. Unlike, a single mode that is observed in thick metal film, thin metal films exhibit two types of modes for the …
Posted on Wed 01 June 2011 in Plasmonics • Tagged with electromagnetism, FDTD, MEEP, octave, photonics, Plasmonics
Particles scatter and absorb electromagnetic radiation. One often needs to compare the amount of scattering/absorption/extinction for particles of different shapes, composition, sizes and incident light properties (polarization, frequency and angle). In this regard, the concept of cross-sections comes into picture. There are three types of cross-sections, 1) scattering …
Posted on Tue 10 May 2011 in Plasmonics • Tagged with electromagnetism, FDTD, MEEP, octave, photonics, Plasmonics
In MEEP (1.1.1), dielectric structures are often created by constructive geometry (adding and subtracting primitive shapes). The primitive shapes that are allowed are blocks, cylinders, ellipsoids and cones. To create a complex shape, one has to decompose the geometry into these primitive shapes. Over the weekend, I was …
Posted on Wed 27 April 2011 in Plasmonics • Tagged with electromagnetism, FDTD, Free Software, Matlab, MEEP, octave, photonics, Plasmonics, SERS
[latexpage]
The aim of this post is to share my experience in incorporating dielectric function of metals such as gold and silver into MEEP (a free finite difference time domain package) code. The incorporation is not an easy task and can be daunting for the first time user.
Metals such …
Posted on Sat 09 April 2011 in Plasmonics • Tagged with FDTD, Molecular Machines, photonics, Plasmonics, SERS
Metal nanoparticles exhibit localized surface plasmon resonance (LSPR). One can think of LSPR as resonance of electron sea oscillations driven by incident electric field. This is similar to the way a spring-mass system attains resonance under external periodic driving force.
The result of this plasmon resonance is enhanced dipole moment …
Posted on Tue 23 November 2010 in Plasmonics • Tagged with electromagnetism, FDTD, Free Software, photonics, Plasmonics
It is important to know the magnitude and distribution of electric field near the metallic nanoparticles at plasmon resonance. One can look at the electric field and say whether the plasmon mode is dipolar or higher order mode such as qudrapolar mode. At many times one is also interested to …
Posted on Wed 26 May 2010 in Plasmonics • Tagged with DDSCAT, electromagnetism, Free Software, Plasmonics
Discrete Dipole Approximation (DDA) is an important tool in plasmonics research. Using DDA, one can calculate scattering properties of nanoparticles at various wavelengths, polarizations and surrounding medium. The specialty of DDA is that one can calculate scattering properties of irregular shape particles (particles other than spheroids). DDA is based on …