Recent content by free_electron

When the weibull shape parameter beta is <1, the pdf is divergent at t=0 due to negative exponent of beta -1. With such a divergent distribution is it meaningful to use Weibull for beta <1?

okay, I hadn't checked most of the periodic table yet :P But even band gaps have a limited range, add to that a limited range of distances from the Fermi to the vacuum level. Do these ranges come from somewhere? Thanks.

This is the case with metals semiconductors polymers and ceramics I have checked on the web. Still looking for exceptions...

When an electric field is high enough, electrons are not so easily confined to molecules or atoms. This has been the basis of field ionization for mass spectrometry. But what if the field is not enough to ionize, but close. Would it be easier to ionize the atom or molecule with less energy? Any...

Thanks, all. I would be interested in any reference which solves Schrödinger's equation for a photon going through 2 or more slits. TIA.

Okay, so a single photon exhibits all the maxima and minima simultaneously? What about the photon wavefunction just before and just after the two slits?

What is the current interpretation of the interference of two plane waves in the photon picture? Does a photon still possesses the properties of its plane wave form? What is the meaning of the intensity maxima and minima?

http://www.ph.utexas.edu/~schwitte/PHY362L/QMnote.pdf I thought the attached was a nice tutorial on Fermi Golden Rule. f

Agreed. :smile: Thanks, f

Just to make one more thing clear, the lifetime does not indicate a fixed time after which a state decays, it is a measure of the distribution of such decay times (like a standard deviation).

I think we should include that the lifetime IS the measured quantity in the relevant experiments. No energy transition takes zero time; there is always a lifetime. The textbook example has always been quoted, for a stationary state, lifetime (delta_t) is infinite, so the energy is a fixed value...

Yes the experiment is done a number of times, the uncertainty product relates to time and energy as well. For example, the energy state decay is not instantaneous but has a characteristic lifetime delta_t which can be correlated to the energy transition uncertainty (~delta_E) from the...

Does the uncertainty principle provide an estimate of the uncertainty of when a photon is absorbed in a transition corresponding to an energy difference of delta_E=E_final-E_initial? This uncertainty being roughly delta_t= Planck's constant divided by delta_E? So for example, if delta_E = 5...

Thanks for the paper link, very interesting. The conducting AFM is telling, since it always detects current through the dielectric, just a matter of degree of uniformity.

HfO2 is considered to be used as a dielectric but if it crystallizes locally its electrical properties becomes unstable. This happens around 700-800 C, which is below where most semiconductor anneals require. Shouldn't this preclude its use?