HomerReid / scuff-em

A comprehensive and full-featured computational physics suite for boundary-element analysis of electromagnetic scattering, fluctuation-induced phenomena (Casimir forces and radiative heat transfer), nanophotonics, RF device engineering, electrostatics, and more. Includes a core library with C++ and python APIs as well as many command-line applications.
http://www.homerreid.com/scuff-em
GNU General Public License v2.0
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[scuff-neq]: Regarding calculation of Maxwell-stress tensor for fluctuation induced forces #182

Open chinmayCK opened 5 years ago

chinmayCK commented 5 years ago

Hi Homer,

I have been interested in angular momentum of thermal radiation especially from non-equilibrium systems and your work on torques and forces (https://arxiv.org/pdf/1708.01985.pdf) is quite helpful as a starting point. I am researching along these lines and I had a question with respect to these calculations with scuff-neq tool.

In general, for circularly polarized monochromatic light (~ E x + iE y), if we look at the spectral Maxwell Stress Tensor, the correlations are complex valued. In fact, the Stokes S_3 parameter which denotes the handedness, is proportional to imaginary part of correlations <Ex*(w) Ey(w)> which is non-zero for above circularly polarized light. In scuff-em, all the components are always real-valued and spectral tensor is symmetric. Could you tell more about the underlying symmetrization that makes it real valued ?

Many thanks Chinmay.