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Feb2313 08:41 AM
ZapperZ

1 
26,191 
I want to know ... what happens to silicon when some impurity is added to it.
Where does silicon goes??

Nov913 10:55 AM
phyzguy

6 
1,000 
So, I have a basic/general question here. I understand that, for example, the QED Langrangian has U(1) gauge symmetry....

Nov813 11:58 PM
dfttheory

1 
664 
For a nonmetal what determines thermal conductivity is the propagation of lattice vibrations. As T increases these...

Nov813 07:41 AM
DrDu

3 
782 
I've seen these things for sale on the web.
http://www.amasci.com/neodemo.htmlhttp://www.kjmagnetics.com/safety.asp...

Nov713 02:13 AM
sinromagnet

6 
3,255 
I am interested in the following scenario.
Suppose that you have a composite system, e.g. ion, atom or whatever...

Nov513 03:46 PM
mfb

3 
735 
Why energy level is higher on p side of pn junction diode as compare to n side of same

Nov513 10:49 AM
physics.cie

4 
990 
Ashcroft & Mermin, Solid State Physics, page 315:
"According to the Bloch theory, an electron in a perfectly periodic...

Nov513 09:48 AM
UltrafastPED

3 
863 
As far as I understand: In the Drude model we take the electron to be moving in a random direction after each...

Nov513 06:45 AM
UltrafastPED

3 
980 
Semiconductors is said to be energy bands where they are many quantum states the electrons can have. What other...

Nov413 04:27 PM
kye

0 
715 
Does this construction even make sense? By definition it is a surface of constant energy in kspace, so for the free...

Nov413 04:16 PM
mfb

1 
1,026 
One line between (+). Two lines between (++). Zero line between (). \gamma number of nearest neighbours. Why we...

Nov413 08:06 AM
1ndranil

1 
1,797 
In the harmonic approximation, why is the volume of a crystal not temperature dependent? Does it have something to do...

Nov313 01:18 PM
DrDu

1 
799 
Just one short question about something I didn't understand in my book: "At low temperaturs only vibration modes where...

Nov313 01:16 PM
DrDu

1 
724 
I read an article that anion vacancy act as a 'holekiller' which prevents ptype doping.
I couldn't understand...

Nov313 09:11 AM
Useful nucleus

1 
599 
Good day,
I was recently asked to look into the process of thermal annealing of thin metal films in order to induce...

Nov313 07:33 AM
Verdict

1 
651 
Phonons are quantized lattice vibrations. They are travelling waves of the form
exp(ikr) taken to satisfy periodic...

Nov213 02:04 PM
DrDu

7 
1,101 
I have this question on the calculation of the geometric phase (Berry phase) of a parallel transporting vector over...

Nov213 11:09 AM
fzero

1 
826 
Hi all,
There are 2 points I do not get:
1. I read something saying that phonon is an energy packet of "heat...

Nov113 02:17 PM
DrDu

3 
880 
Why is the Fermi level a constant in thermal equilibrium?
just like PN diode (P=material 1 ; N=material 2)
the...

Nov113 09:23 AM
wantommy

0 
946 
This occur when two phonons interact and the sum of their momenta add to a new wavevector outside the new Brillioun...

Oct3113 01:59 AM
DrDu

2 
870 
I was wondering why the valence electrons aren't free to move in insulators? Thanks for any help in advance.

Oct3013 06:35 PM
hokhani

3 
971 
Hi all, I was wondering mathematically how stimulated emission works, could someone please explain it more concisely...

Oct3013 01:33 AM
king vitamin

4 
808 
Dear PF,
I'm trying to calculate the anisotropy constant of a ferromagnetic material. Then, of course, I need to...

Oct2913 04:18 PM
Superposed_Cat

1 
801 
Can we apply the concept of phonons and Debye Model in case of amorphous and polycrystalline solids??
...

Oct2913 03:03 PM
DrDu

4 
1,806 
When a transition from valence band to conduction band happens (in a directgap material), how the momentum is...

Oct2913 10:35 AM
Cthugha

3 
854 
Say an electron tunnels from one state, through a tunneling barrier, to another state.
Is the spin of that electron...

Oct2613 09:37 AM
ZapperZ

2 
1,074 
I am reading the book "Lecture notes on Electron Correlation and Magnetism" by Patrik Fazekas.
It says, "The...

Oct2613 08:28 AM
sam12

0 
918 
How is the cell constant "d" related to the cell parameters? I know that for the smallest possible diffraction angle d...

Oct2513 04:45 PM
UltrafastPED

1 
784 
I have done several exercises concering periodic potentials in crystal. Especially I did one, where I had to show that...

Oct2513 01:32 AM
DrDu

3 
1,080 
For a free electron gas the procedure for determining the density of states is as follows.
Apply periodic boundary...

Oct2413 09:39 AM
nasu

4 
979 
I understand what nuclear binding energy is and its importance in nuclear weaponry an the fueling of stars, but why,...

Oct2113 10:02 PM
Drakkith

6 
1,271 
Are there anybody doing some research on quasicrystals ,especially its mechanical property?
I am just wondering why...

Oct2013 10:11 PM
Timney

2 
741 
My book has a discussion of how the Bragg model can explain the origin of energy band gaps in solid. I have attached...

Oct1913 05:19 PM
Simon Bridge

15 
8,097 
It is mentioned that in optical tweezers the dielectric particles are attracted to the gradient of the laser's...

Oct1913 12:31 PM
pjbeierle

3 
1,061 
hello again physics forums. how will i be able to construct the band diagram of HEMT (and other types such as pHEMT...

Oct1913 11:36 AM
lubin1

0 
705 
I know what is lattice constant but it has been given that nano particles have reduced lattice constant due to huge...

Oct1913 10:47 AM
UltrafastPED

3 
957 
Can we apply the concept of phonons and Debye Model in case of amorphous and polycrystalline solids??
...

Oct1913 08:26 AM
Claude Bile

3 
1,906 
Greetings everyone,
I am confusing the definitions in the title of the post all the time. I have books about...

Oct1913 08:10 AM
Claude Bile

3 
1,838 
Hi all,
I use Transiesta package for DFTNEGF nanoscale transport calculations. I wondered if there is a very very...

Oct1813 12:00 AM
simsCity

0 
922 
Hello Physics Forums.
Our professor asked us to do a program on constructing the band diagram of BCC and FCC for...

Oct1713 02:34 PM
UltrafastPED

1 
1,050 