Recent content by zhanhai

Is it correct that a crystall of simple lattice (lattice with primitive cells each having only one atom) cannot be antiferromagnetic? In other words, the antiparallelism must occur between atoms within each primitive cell. Thanks.

Does a type I superconductor has to be single crystal? If not, is there any change in its Tc when it becomes polycrystal? Thanks.

To https://www.physicsforums.com/members/hallsofivy.331/: Thank you for your reply! Suppose F is similar to Sturm-Liouville form: y''+p(x)y'+q(x)y=h(x), where p(x) has no more than first-order singularity point, and q(x) and h(x) each actually has no singularity; then, is F "well behaved"...

I don't quite understand "When we observe an electron it is always a localized excitation in the electron field". First, it would depend on what is measured. If you are measuring the position of the electron then the statement could be right. If on the other hand you are measuring the...

Differential equation: F(y'',y',y,x)=0, y=y(x). Now, there is g=g(x) with F(g'',g',g,x)=δ, where δ is small. Then, can g(x) be taken as an approximate solution of F(y'',y',y,x)=0?

I had read through each of the posts on the first page of the search result list before I wrote my previous replying post.

I have just read through the BCS paper, which gives basically the same explanation (possibly except the Bose-Einstein condensate). I do not think it is a microscopic explanation, since it is too general. So I searched "zero resistance" in PF and as many as 135 posts (including this one) turned...

MisterX, thank you very much. I agree with your clarification and explanation.

Let A(k,x) be a Bloch function, then is the integral <A(k,x)|dA(k',x)/dx>=δ(k,k') ?

Semi-classical wave packet, or localization of wave function (WF) of electron, works well as basis for explaining electron transportation in semi-conductors. But it seems failed in explaining superconditivity and normal conductivity in a single crystal. In addition, it is doubtful whether the...

This makes very good sense. But it assumes that the wave functions (WFs) of the two particles cannot be separated. The general validity of this assumption should be by itself related to the subject question. On the other hand, when the two particles' wave functions can be separated, the...

There is actually no description on quantum mechanical description of metallic conduction at this wiki webpage.

Suppose that a static electric field E is applied on a conductive crystal. Then, how quantum mechanics describes the electron movements in the crystal? I have been trying to find an explanation, but have not found any. As I understand it, we could treat the E field as a time-dependent...

Why wavefunction (the square of its modulus) of an electron is not seen as a measure of substance/charge distribution of the electron?

I am confused. When an electron absorb a phonon, it receives both the energy and momentum of that phonon; and a phonon mode is characterized by its energy and momentum (wavevector), and all modes in one branch have their energy-wavevector characteristics face, correct? Second, as an electron...