Recent content by mcodesmart

If you use the drude model for an oscillator and include a damping term (modelled as a fictional force on the dynamical equation), you can allow for broadening and the peak of the resonant absorption frequency is not a sharp peak but rather a broad peak that is be centered around some maximum...

The scattering in general is given as follows: I(K) \propto S(K) = 1 + N/V \int g(r) e^{iK\bullet r} dr

The dimensions of the plate, (10mmx 10mm) and made from very flat and polished Si wafers. No voltage between them but I understand van dew Waal interactions is an issue at those lengths?

Any ideas on how one can make a small gap (~10-50nm) between two parallel plates and maintain a known distance between them. I have two very flat surfaces and I would like to maintain a small gap (known gap) across them. I searched in the literature but I came up with nothing so if you have any...

You mind sharing your results so we can take a look as well.. I am curious and also, what material is it..

O.D measurements depend on sample length. 10^{-OD} = I(z)/I_o replace I(z) with I_o e^{-αl} and work it out.. The answer is OD = 0.434 αl

because an electron state in a metal conduction band has a de-localized wave function. It can contribute to conduction without having to transition to another band as in a semiconductor. Of course, it is more intersting to ask what happens when an electron is removed as in photoelectric effect...

Attached is the experimental data for GaAs. Please take a look and I would be interested in your comments. I think that exciton absorption that you mentioned are occurring above the band gap energy. You can also see the threshold behavior that I mentioned.

Electrons transfer energy through a wire. Absolutely. This is called electron scattering.

I have attached a figure from Ashcroft and Mermin. Do this. In the case of 2D, take the reciprocal lattice and you draw a circle or radius k from the center. How many electrons states you would have in that area encircled in k-space? If you can figure this out, you can easily find the answer...

The hole concept is related to a missing electron in the valence band. The valence band of a metal is completely filled and the electrons in the conduction band are FREE to begin with. Therefore, there is no such thing as a hole in metals.

I think you are getting lost in the details. Let me give you a bigger picture to always keep in mind. The reason we care to understand phonons is because they carry and transfer energy. And knowing how and in what capacity they carry energy allows us to calculate the heat capacity and thermal...

The band gap is the minimum photon energy where you can see the absorption. it is characterized by a threshold behavior. The aborption below the bandgap should be zero (at least for direct band gap semiconductors, (ALSO PLEASE NOTE Franz-Keldysh Effect). The absorption above the band gap is...

I am not familiar with this material. Is it similar to graphene dispersion relation, where you have a discontinuity at k=0 (or infinite effective mass). To know the absorption, you must do the following. Using Fermigolden rule. calculate the transition rate for an electron from one band to...