Recent content by Pete99

Not exactly. I do want to use the variables that contribute the most to the actual fit. But I want to chose the parameters from a set of parameters that have some physical meaning in my problem. Let's say that my model has three physical parameters that contribute to the output as x=[h_1 h_2...

Thank you chiro for your your detailed response. Sorry for the notation if it is not very rigorous, and correct me if something I say is directly wrong. I guess I forgot to mention that the vectors (columns from H) that I want to use are already defined and have some physical meaning. As far as...

Hello all, I have a set of measurements that I want to fit to a linear model with a bunch of parameters. I do this as \theta=(H^TH)^{-1}H^Tx, where θ are the parameters and x is the set of measurements. The problem is that I'd like to reduce the number of parameters in the fit. I'd like to...

I guess that to support the charge distribution in a surface plasmon polariton you need an electric field in the direction of the propagation. TE modes only have transversal electric fields.

The guided wave will generate fields in the surface with an spatial variation given by the inplane wave vector k_i. If k_i>k_o, the wave vector outside, propagation will not be allowed because you cannot find any direction such that the projection of k_o onto the surface matches the inplane wave...

I am not sure if I understand your question. When you have a guided wave due to total internal reflection, the in plane wave vector is larger in magnitude than the wave vector in free space, so that propagation is not possible. If you have a periodic perturbation at the surface, you will...

As you said, the k in a crystalline solid is a wave vector, much like the wave vector in a propagating electromagnetic wave. In the case of an E-k diagram, k corresponds to the wave vector of the electronic wave function. You can create a wave-packet by adding a number of waves with different...

Any idea?

My understanding is that thermal energy is the mean energy of the random motion of the particles in a system. So I would say that the energy of the individual particles is quantized, but that thermal energy, being the mean value, does not necessarily have to be quantized. But I am actually...

I'd say that the low probability of emitting in the low frequency region is because the smaller number of modes in which you can emit. You can find a good explanation in http://hyperphysics.phy-astr.gsu.edu/hbase/mod6.html"

Hi, I have read in different references that trap assisted SRH recombination is non radiative and gives the energy to phonons. However, I have not been able to understand why is not possible to generate photons in this case. I mean, can SRH recombination give the energy to photons? What...

Thanks! Now it is clear.

What do the indices 6 and 13 stand for in 6,13-pentacenequinone? I know that is related to the position of the substituents in the molecule, but I cannot figure out how to interpret it. Can some one point me to a reference where the basics the nomenclature are explained? Thanks,

Maybe I did not make myself clear, or I am totally wrong, but in an atom such as nitrogen in the ground state, the electronic configuration would be 1s2 2s2 2p3 To maximize S we would have the three electrons with parallel spins in the three degenerate p states, but then L would be zero...

Thanks for your answer! Is it always the case that the combined angular momentum of a set of degenerate states adds to zero? I know that it is zero for an atom (for example px, py, pz).