Electric field at localized plasmon resonance using MEEP

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 …

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van der Pauw correction factor

Posted on Sun 08 January 2012 in Electronics

The van der Pauw Method is a technique commonly used to measure the Resistivity and the Hall Coefficient of a sample. A correction factor goes into calculating the resistivity as described in van der Pauw paper. A iterative method is generally used to calculate the correction factor and this correction …

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Surface plasmon dispersion relation for thin metal films

Posted on Wed 07 December 2011 in Plasmonics • Tagged with electromagnetism, octave, Plasmonics


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 …

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All entries of array except certain indices in octave/matlab

Posted on Wed 07 December 2011 in Misc • Tagged with Matlab, octave

In Octave or Matlab, some times one needs to eliminate certain elements in an array.

For example, if

a = [10,20,30,40,50,60];

and suppose I want to create a matrix "b" such that it has all the elements of "a" except 20 and 40. This can be …

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Scattering / extinction / absorption cross-sections of silver nanowires (infinite cylinders) using meep

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 …

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Arbitrary 2d shapes in MEEP

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 …

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Plasmonic materials in MEEP

Posted on Wed 27 April 2011 in Plasmonics • Tagged with electromagnetism, FDTD, Free Software, Matlab, MEEP, octave, photonics, Plasmonics, SERS


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 …

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Electric Field in Metal Nanoparticle Dimers

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 …

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Charge density in metal nanoparticles at plasmon resonance

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 …

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Spoof Plasmons / Designer Surface Plasmons

Posted on Thu 07 October 2010 in Plasmonics • Tagged with MEEP, FDTD

Aim of this article/post: To 1) introduce the concept of Designer surface plasmons or Spoof plasmons and 2) Dispersion relations and Visualization of the fields using MEEP code. (Some of the text/simulations are taken from my paper in the area of DSPs.)

Surface Plasmons are electromagnetic waves that …

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