Recent content by erst

Yup, you're done if that's all the information provided. Put m_0 in the denominator.

The wavefunction contains complete knowledge of the system, so I think yes it should be possible to compute all materials properties in principle. But is it meaningful to talk of a photon wavefunction? The Schrodinger equation does not apply to them. More advanced formalism is needed (fields...

marcusl -- The current picture is fully equivalent to the voltage picture. See e.g. Streetman Ch. 7. It's meaningless to say I_c is not caused by I_b; local (steady-state) neutrality demands it, so it's just as causal as a bias-based description. It's helpful to think of what would happen if...

What a BJT does: There's a bias between the emitter and collector. But current can't flow because the base presents an energy barrier to carriers (e.g. for NPN, the P region is higher than N in an energy diagram). But if you were to inject current into the base, this charge would build up and...

If we have a bunch of electrons in the conduction band, there's a probability that some will fall into valence band. When that happens, it's a recombination event - i.e. the a hole is filled and disappears. The more electrons you have, the more falling electrons you have. So if the number of...

How does one interpret band structures (i.e. E,k solution pairs for a given Hamiltonian) for a non-primitive cell? I was looking at these slides: http://www.tcm.phy.cam.ac.uk/castep/CASTEP_talks_06/clark2.pdf Slide 9 has the "normal" silicon band structure obtained with a primitive cell...

Two very different things. Field emission from the surface of a metal involves ejecting the electron to the vacuum level, i.e. it becomes entirely free from the metal and goes off into the environment. This a large energy compared to the thermal energy so a electric strong field is needed...

You need to draw it with the vacuum level to see it properly. Basically, the semiconductor needs to have a depletion width of positive ions to match the charge of the electrons in the Schottky metal. If there isn't enough "space" to do this because the semiconductor is terminated before...

But what's on the other side? If you just have a floating piece of semiconductor, then it can just adjust its chemical potential as needed. More likely, you would have a complete circuit, which means there's another metal contact on the other side of the 0.1um semiconductor. The Schottky...

Total energy (potential + kinetic) is unchanged. Potential energy is lower inside the well. If it manages to tunnel outside, then there is a transfer - potential goes up and kinetic goes down. In terms of 'structure', you need to look at the form of the Schrodinger equation. Kinetic energy...

It matters significantly for the calculations I'm trying to do. I want to get the equilibrium band alignment of a metal-insulator-metal structure (i.e. a tunnel junction). Depending on how the insulator is aligned with the metals, the electrons at the metal Fermi level see significantly...

Does the (intrinsic) Fermi level of an insulator HAVE to lie very near the middle of the band gap? I know it might deviate slightly if electrons and holes have different effective masses, e.g. in Si. But can it be radically different? For example, are there insulators with 5 eV band gaps that...

Thanks, that clears things up a lot. When does the mean-field approximation break down? Is the many-electron wavefunction useful for real-world calculations? In applications, I've never encountered anything but single particle descriptions (hence my ignorance).

I don't know about OPVs specifically, but MIM structures develop a built-in bias with asymmetric electrodes because the difference in chemical potential (due to different work functions) causes charge flow until the chemical potential is flat everywhere. If there is no circuit connecting the...

What is the "many-electron wavefunction"? In the introductory picture, the wavefunction represents the particle's probability amplitude and its modulus squared is probability density. It integrates to 1, representing the fact that, with certainty, there's an electron somewhere. What, then...