Why isn't the constant force problem in QM classes?

Gokul43201

Besides FETs, there's a whole host of other places where you see approximations to triangular wells or linear potentials - in modulation doped heterostructures, metal-semiconductor interfaces, biased junctions, etc.

And in most of these places, the linearity of the potential does not come out of the approximation used to model the system (in any case, such an approximation is chosen for a reason) but is the expected/designed profile.

aav

See J. J. Sakurai, Modern Quantum Mechanics, revised ed. Problem 24, Chapter 2.

Gokul43201

And the bit about gravity-induced interference between neutron beams (also in Ch. 2)

Kane O'Donnell

I should point out here that although almost everyone does use the WKB approximation in these cases, there has been a bit of a move in recent times to be more cautious in the application of the FN equation to arrays of emitters. Look at K Jensen's papers on FE - see especially his chapter in Vacuum Microelectronics.

ZapperZ

Yes, I'm aware of that, since I've talked to him a few times and have been looking into why people are using the FN model BEYOND the region of applicability, such as in a high-gradient photoinjector.

I think Kevin and I share a common "bond" - we're both refugees from condensed matter working in accelerator physics. :)

Zz.

DaTario

Regardig what most of you have said:

is acceleration and mass observables? If so, why force is not an observable ?
Even in Heisenberg picture, equations with operators like force never show up?