WINSPALL software for surface plasmon resonance experiments

One needs to fit the reflectivity curves obtained in surface plasmon resonance experiments with theoretical models. A free software (for non commercial use) called Winspall exactly does that. According to the developers, WINSPALL is a PC based software which computes the reflectivity of optical multilayer systems. It is based on the Fresnel equations and the Read More …

My list of most used packages for ubuntu

To install octave, gnuplot,numpy,scipy,matplotlib,gcc-4.2-base, gfortran sudo apt-get install octave gnuplot \ ipython python-numpy python-scipy \ python-matplotlib wine gcc-4.2-base gfortran-4.2 To install graphics programs: gimp, imagmagick and inkscape sudo apt-get install inkscape gimp imagemagick To install most of the multimedia requirements  sudo apt-get install vlc mozilla-plugin-vlc gstreamer0.10-ffmpeg \ gstreamer0.10-fluendo-mp3 gstreamer0.10-fluendo-mpegdemux \ gstreamer0.10-plugins-ugly gstreamer0.10-plugins-ugly-multiverse \ gstreamer0.10-plugins-bad gstreamer0.10-plugins-bad-multiverse Read More …

Radiation from an oscillating dipole

The electric field from an oscillating dipole is given by:, where is the position vector, is the frequency of dipole oscillation, is the dipole moment. The two terms in the electric field consists of 1) near field (area near to the dipole) and 2) far field (area far from the dipole) contributions. Far field falls Read More …

Surface Plasmons (SP’s)

Surface plasmons (SP’s) are electromagnetic waves that propagate at the interface between metals (such as Ag, Au ) and dielectric material. Here I have simulated the propagation of surface plasmons on Ag-air interface, the color indicates the magnitude of electric field (blue for positive and red for negative).  I have used MEEP  (a FDTD program Read More …

Plasmonic coupling of electromagnetic energy in hexagonal array of silver nanorods

A cool animation which I reproduced from W.M Saj, Optics Express, Vol 13, 13, 2005 using freely obtained FDTD software (MEEP). It demonstrates the propagation of electromagnetic energy in hexagonal array of silver nanorods due to plasmonic coupling. The source is offset from the center and the energy is propagated in an interesting snake like Read More …

Split, collate, watermark and password protect PDF documents using portable pdftk

To split, collate, watermark and password protect pdf documents, I use pdftk portable app. pdftk is one of numerous applications that come with  PortableApps.com free software. This platform can be installed on any portable USB drive and can be run on any computer without administrative privileges. More information can be found here and here. A Read More …