Plasmonic Materials in MEEP > 1.2

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 …


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Doorbell with NRF24L01 and Arduino

Posted on Fri 29 May 2015 in Electronics

My current apartment does not have a doorbell (Its strange but it is true). I went ahead and built a doorbell using two arduino pro-minis and two NRF24L01 transceivers. The melody to be played when a guest presses a button can also be controlled. I have four melodies programmed in …


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Airtel tune on arduino

Posted on Thu 21 May 2015 in Electronics • Tagged with Arduino

For my doorbell project, I needed some melodies to be played on arduino. One can takes notes of a melody and write a corresponding arduino code.

I like airtel tune and wanted to play it with arduino. I got the notes from https://www.youtube.com/watch?v=3m5j5UIRqQc

Here …


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Controlling Rigol Dp832 with python

Posted on Fri 08 May 2015 in Electronics • Tagged with Instrumentation, python

DC power supplies are very handy for electronic projects. They help to apply bias/voltage to a device. Controlling it by a computer by a program is helpful in advanced projects where timing and accurate control is an issue.

I got my hands on a RIGOL DP832 which is three …


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Hacking Weighing Scale to Upload Weight to Plotly using Raspberry Pi

Posted on Sat 11 April 2015 in Electronics • Tagged with python

I have been interested in monitoring and keep track of my weight. In the past, I have used different phone apps to track my weight. They work reasonably well, but I was thinking of reading weight data directly from my weighing scale and upload the data to an online database …


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Controlling Newport 1918 Power Meter with Python

Posted on Sat 04 April 2015 in Electronics

Optical power meters in-conjunction with a detector are used to measure power from a laser source or monochromatic output.

At work, we use Newport 1918 power meter. This power meter comes with its own software. However, I was interested in controlling this instrument with python.

I wrote a python module …


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Controlling SP2150i monochromator with Python/PyVisa

Posted on Fri 19 September 2014 in Electronics

Monochromator is used in optics research where a narrow bandwidth of light is required to be illuminated on a sample. I work with Princeton Instruments Acton SP2150i and needed a python program to control it.

I found the manual here and on page 9-10, I saw the serial commands for …


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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

[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 …


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