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If you are seeking help with a...

Feb2313 08:41 AM
ZapperZ

1 
25,928 
Why does the quantum defect depend only weakly on the principal quantum number n?
The dependence on l is strong....

Jan1614 07:30 AM
DrClaude

1 
746 
This question relates to rate constants of transition events. The transmission coefficient κ reduces the value of the...

Jan1814 02:02 AM
DrDu

1 
668 
Suppose we have a Type II superconductor that contains a knotted Abrikosov vortex. How long can we expect this to...

Jan2114 02:29 AM
M Quack

1 
560 
Dear all,
I have a problem about the eigenvalue of the system and the eigenvalue of the part of the system.
...

Jan2114 10:28 PM
Douasing

1 
622 
In an article I am reading gold wires a fabricated on top of a substrate using electron beam litography.
How exactly...

Jan2114 10:27 PM
Hypersphere

1 
560 
Dear all,
I have a question regarding electronic transport in a device with length smaller than the phase relaxation...

Jan2614 03:35 PM
UltrafastPED

1 
595 
I'm used to astrophysics, where flux tubes in highly conductive materials are said to be "frozen" to such materials...

Jan2814 05:44 AM
M Quack

1 
676 
Hi All,
I am preparing for PhD quals and have been looking at problems from other universities. I came across this...

Feb114 06:49 PM
Astronuc

1 
731 
In Bragg’s spectrometer used to determine the wavelength of X – rays why should we make use of only NaCl crystal,cant...

Feb514 05:48 AM
M Quack

1 
749 
For two electron system ##\vec{S}_1##, ##\vec{S}_2##
\mathcal{H}=J\vec{S}_1\cdot...

Feb514 05:41 AM
M Quack

1 
671 
Anyone know how hydrogen bonding in water can enhance "density fluctuation" ?
And in first place What is "density...

Feb1214 03:14 AM
DrClaude

1 
934 
I am bit confused by how to approach this concept with mean field theory. As I understand a symmetry break (like a...

Feb1114 12:48 AM
DrDu

1 
764 
Hello all,
I have been learning to use FDTD to model light interaction with various materials. I've successfully...

Feb1214 01:16 AM
DrDu

1 
867 
I think most of you are familiar with this model (sum runs over nearest neighbours):
H = J ∑S_iz * S_jz
It...

Feb1414 05:43 PM
Hypersphere

1 
796 
Hey all,
I was studying stimulated emission in lasers and I had a doubt regarding the same.
When the electron...

Feb1514 08:13 AM
Simon Bridge

1 
958 
I have a molecular dynamics code and I want to model the reaction of O with Mg to form MgO at arbitrary temperatures. ...

Feb2014 07:38 PM
Useful nucleus

1 
859 
Hi All,
Greetings!
I have a 3d material and I use result from first principal for getting the potential...

Feb1914 12:41 PM
cgk

1 
795 
I'm supposed to be working with an STM in the coming weeks to determining the Fermi Level of some semiconductor...

Feb2314 03:34 PM
ZapperZ

1 
837 
Should I use Quantum ESPRESSO or Material Studio?
I want to compute some properties in Material

Mar1514 03:19 AM
tshuxun

1 
800 
Hi all
Can someone please describe how the form factor used in Rutherford scattering is applicable to neutron...

Mar2214 03:41 AM
M Quack

1 
601 
Hi,
could someone direct me or recommend me some materials which deal with those problems?
I would like to get...

Mar2314 08:50 AM
ZapperZ

1 
553 
Hi all,
could you suggest me references that can help me in the following calculation?
I would like to see how to...

Mar2614 02:28 AM
DrDu

1 
655 
Suppose you have a body floating in a rotating superfluid. Maybe a speck of dust. Would it rotate?
What if you...

May614 07:10 PM
Greg Bernhardt

1 
548 
Hi, I have problems with the following:
Number of modes for a 2d crystal with one atom per primittive unit cell.
...

Apr514 01:56 PM
DrDu

1 
543 
Does atoms in a crystal have energy states like electronic states? it is according to Einstein relation for harmonic...

Apr714 11:55 PM
jlopezfis

1 
483 
I cannot wrap my head around this stuff. Sorry if long post.
I understand that emission lines come from a higher...

Apr814 03:23 AM
Zarqon

1 
471 
How would react ion of some gas (low energy anion or cation) in vicinity of a grounded metal surface or in vicinity of...

May914 02:19 PM
mr.smith

1 
762 
Phonons are said to be the result of the quantization of crystal waves.Let the function u=u_0...

Apr1014 06:46 AM
Zarqon

1 
525 
I read this:
I don't see why the electron spin affected the number of lines to go up in some atoms and not in...

Apr1414 09:02 AM
DrClaude

1 
535 
Hi,
Could anyone explain how the affect that PN junction depth has on the performance of a semiconductor device?...

Apr2014 12:20 PM
M Quack

1 
534 
Hello,
I'm currently writing a chemistry program. The user can create any kind of atom he can imagine, and then...

Apr1914 09:04 PM
SteamKing

1 
543 
Hi all
I was trying to understand the BornBethe approximation related to cross sections for atomic and molecular...

May414 10:46 PM
Greg Bernhardt

1 
625 
hello everyone..
1) what is the magnetic properties for indium oxide? i hope that it has ferrimagnetic properties...

Apr2414 10:39 AM
UltrafastPED

1 
442 
Hi,
I am numerically solving the 2D effectivemass Schrodinger equation
\nabla \cdot (\frac{\hbar^2}{2} c...

May614 11:48 PM
Greg Bernhardt

1 
556 
I know that at early stage (around 1999), GW implementation uses Matusbara frequency to help calculating self energy,...

May2714 02:03 PM
Greg Bernhardt

1 
645 
Hi,
I've been reading about critical exponents and how they're related in any system. I've seen how, for example,...

May1314 01:36 PM
Timo

1 
616 
I am reading a book about the interaction between atom and photon. I don't understand the following statement:
"for...

May1314 03:38 AM
Zarqon

1 
561 
I am learning Ashcroft's Solid State Physics. In the Electrons in a Weak Periodic Potential, I got some problems.
...

May1314 10:47 PM
Simon Bridge

1 
579 
Orthogonal plane waves can be used to expand Bloch waves. It is better than plane waves because it converges more...

May1814 09:49 AM
bsmile

1 
524 
I know one can find the "near field" length of an illuminated diffraction grating by calculating the Talbot Length,...

May1614 11:18 AM
Claude Bile

1 
534 