Homework Statement
We must calculate the Fermi energy of metallic potassium at 0K. We have aleady found the number of atoms per m cubed, we are told that each atom contributes one electron to the free electron gas.
Homework Equations
Fermi energy = ((hbar^2)/2m)(((3Pi^2)N)/V)^3/2
The...
Homework Statement
(1) For the cubic 3D infinite-well wave function,
\psi(x,y,z) = A sin(n\pix/L)sin(n\piy/L)sin(n\piz/L)
Show that the correct normalization constant is A = (2/L)^{3/2}
Homework Equations
Note: The Pi's above are not meant to be superscript, and each n relates to...
I believe i have got to the bottom of this. It is about how many electrons there are in the primitive cell of the lattice. If there is an even number (due to the two spins an electron can have) then there are no empty states to allow electron movement and we have an insulator. If there is an odd...
Im not sure what hafsa is saying exactly, but in response to ZzapperZs reply the bloch theorem just shows us that a periodic potential causes the separation of energy levels into bands. But a metal is a crystal structure with a periodic potential so why does band theory say that there is not...
The periodic coulombic potential from the regular array of atoms in a crystal lattice causes the electron wavefunctions to split into two 'bands' of allowed energy states. The bands are just a range of energies where the density of states is large and the bandgap is the energy difference between...
Thanks for the reply. I am familiar with the screening effect of inner electrons and effective nuclear charge experienced by the outer electrons as a result. So the difference between a metal and an insulator would be that a metal atoms outer electrons are bound more weakly than those of an...
In conducting an experiment to measure the bandgap of n-type Ge using the 4-probe method, heating the sample and measuring the change in voltage across the probes as it cooled, it was necessary to change regularly between the milliammeter and the millivoltmeter setting on the instrument to...
The literature i have on the origins / need for an effective mass of electrons seems only to relate it to the explanation of heat capacity of metals but it seems like the concept has applications far beyond this. Can someone pls provide a more general summary of its derivation and applications...
Its clear from above replies how diffraction is reflection but no one has touched the relationship of the reciprocal lattice and the real lattice particularly. I'm currently still trying to get my head around it but the way i understand it id that when you examine the diffraction pattern from a...
Thats my poor explanation of the problem sorry, i get that the bands are a continuum of states from the k-points in the Brillouin zone. I was asking more about the exact meanings of the two parts of the Bloch function and how they relate to the shapes of the wavefunctions in the bands.