Band structure Definition and 96 Threads

Look at the diagram below, after all that doping, 2 blocks of Si have the same band structure? My understanding of band structure and fermi level is that: Given a block of solid (Please note, not a TYPE of solid, but this PARTICULAR block of solid) it will have its own unique band structure...

i would like to know all the details about the band structure in a semiconductor and in particular what we call : yours sincerly guedman

My question is as follows: if you place an insulator into an applied field, the only thing that will happen is that the potential energy of each band will shift, according to the potential that it is in. Why is this exact same thing not what takes place in conductors? Why do the electrons at the...

I have been contemplating for a few days now about how one could think about the electronic structure of Liquid metals. The cases of an isolated atom or that of solid metal crystal are well known and easy to understand. Though, a google search reveals (to me) that nothing much has come out for...

I have done the computations of band structure of cobalt adsorbed graphene. In 3x3 supercell of cobalt adsorbed (one cobalt atom) graphne, there is opening of band that is gap between conduction and valence band but there is no gap in 4x4 supercell of cobalt adsorbed graphene. I've done this in...

Is it possible for a disordered or amorphous structure to have band structure? I understand derivation of bands from Kronig-Penney model. E.g. does amorphous silicon have a band structure? While amorphous silicon oxide does not have a band structure?

Hello! I'm having my materialphysics exam in a few days, and looking some of the older exams I saw that there are many times questions about band structure and density of states. More specifically there might be a picture of some band structure plus the density of states, like this. Then...

Hello, Is there an established relationship between the diffraction intensity that a sample produces with its band structure? Thanks

Hi! I'm reading about band structure and conduction in regular crystals and semiconductors, and I've hit a few confusing points my book doesn't explain well enough for me. In one part, they're explaining conduction in a 1D crystal with lattice spacing a (and therefore reciprocal lattice...

What are the parameters affects the band gap in a band structure?

Suppose an electron in a crystal(periodic potential) has the Bloch wave function \psi (k_0,x) at t=0. Applying a constant electric field E(at t=0), the electron would still have Bloch-type wave function at any time t with k(t)=-(1/\hbar) eEt+k_0. Now According to this formula for k(t), one can...

I found a lecture on the internet where a LCAO assumptions are used to calculate the phonon band structure. In this lecture (Here) we can find that the true Hamiltonian: H = \frac{p^2}{2m}+V_0(x) where V_0(x)=V_0(x+a) is replaced with the following aproximate hamiltonian: H\cong \sum_n...

In crystalline material, bands arise due to the interaction of electron waves with periodic potentials. Can anyone please explain the origin of energy bands in non-crystalline material..couldn't find relevant links on Google.

"Band structure a result of Pauli"? Professor hopelessly vague or in essence correct? Hello, I'm taking an introductory course on Solid State physics (level: last year undergrad physics) and the professor said one can view the band structure in solids as a result of the Pauli principle...

Dear forum people, I just learned how to get a tight-binding dispersion for graphene: E = +- \sqrt{1+4\cos((\sqrt{3}a/2) k_x)\cos((a/2) k_y)+4\cos^2((a/2) k_y)} But i can not figure out how can I plot that. I want to plot that in the following path: K \rightarrow \Gamma \rightarrow M...

I've been having a very difficult time understanding why band structure is expressed in terms of momentum/crystalline directions. I've included a picture of the band structure of silicon so that you can better understand my question. I think I understand basic crystalline structures and the...

I'm thinking mainly within the context of the useful semiconductors here (Si, GaAs, etc.)... What does it mean for an electron to be in the L or X valley instead of the Gamma valley? If Gamma is the k = 0 point, then momentum p = 0. Does that mean being in L or X means all the electrons...

Hi, thanks for reading my questions. I've been reading and reading and reading and reading and I'm trying to understand the difference between conductors, semiconductors, and insulators at an atomic level. When reading about electricity I often find that metals have a "sea" of "free"...

Hi I've been searching on the web for this two topics, band structure and fermi surface, both of copper. I can't find any of them from a free source, I am doing just a report of my class of introduction to solid state and I just have found this two things in articles that must be bought. If...

how is the relationship between fermi level and band structure of solids can effect electrical conduction properties of a material?

Metal nanoparticles (Au, Ag, Al or ...) can coat on porous silicon, the particles can be located inside the pores or on the silicon micro/nano structures. By applying this type of coating is there any change in band structure of porous silicon? As I've measured the band gap has changed.

Hi everyone, I'm working on random materials which are coincidencely oxides and showing semiconductor behaviour... Some of these are metals and i suddenly realize MOS (which are practically everywhere). I know them, i know how they work and behave still i can't get to understand the effect of...

Hi everybody, I would like to know if someone could explain to me what happens to the refraction index of gold at grazing angle (X-ray applications), and particularly the band structure explanation (if you have it!)... Indeed, I heard that the x-ray telescopes were made of parallel mirrors...

Hi! Is anyone familiar with generating band structures from DFT simulations? I am using graphene, and am trying to plot the electronic structure at the high symmetry points (K, M, and gamma). Grappling to understand this theory, my questions are: 1. Is the location of the high symmetry...

Hii, I was wondering whether there is any correlation between the energy eigenvalues of a single atom (say He) with the electronic band structure of a collection of He atoms. for example, for He atoms the lowest energy would be the ground state, with 2 electrons. So will the lowest band for a...

Dear all, I have been thinking, if insulators have their valence band filled, then which band does the extra electrons go when it is negatively charged?? If it is the conduction band, then it would become a conductor... Similarly, if it is positively charged, there would be a hold in the...

Hi! I'm new here... I'm going to go right to the point. I know that when you take atoms and get them closer together, the discrete energy levels turn into bands. But when I'm facing a band structure plot, such as this one (band structure of aluminum nitride in wurtzite structure)...

Hi! I'm new to the physics forum but I've read a little bit and I'm impressed with the knowledge a lot of people have here. I've tried searching for any topic on my question without any luck. My question is simply what the algorithm is to determine the band structure for a one dimensional...

Hi, Could someone help to explain that why for the 2 D system, like 2 dimensional electronic gas, the crystal momentum k in 2D band structure is defined on a torus? Thanks a lot.:)

Dear all, I want to calculate the band structure of graphene for a unit cell with 8 atoms in the Tight Binding approximation. There is no problem about drawing the band structure for a unit cell with 2 atoms. But by increasing the unit cell size, first brillouin decrease and there is a gap in...

Does anyone have any experience using Gregory Snider's 1D Schrodinger/Poisson solver? I'm trying to do some simulations of a quantum well my group is studying, and I'm not sure if I'm doing something wrong or if the code is buggy or if I'm just interpreting the results incorrectly. Here's the...

Hi, all, I want to calculate the band structure and there is example such like that: BandLinesScale pi/a %block BandLines # These are comments 1 0.000 0.000 0.000 \Gamma # Begin at Gamma 50 2.000 0.000 0.000 X # 25 points from Gamma to X 20 2.000...

Hi everyone! I wanted to ask if in your opinion is it right to say that band structure calculations (and hartree fock calculations) could live in a framework of the fermi liquid theory where quasiparticles are one-electron states (which could be or not could be the case)...

Setup: I'm trying to make the band structure for a planar photonic crystal with finite thickness, i.e., a quasi-3D problem. I only want the x-direction band structure. So, I'm using variable floquet periodic BCs for the x-direction boundaries, and 0 degree floquet periodic BCs for the...

Hi, In all the tutorials of DFT softwares I have encountered computing of the band structure for different systems by using e.g. L-Gamma-X-(U)Gamma circuits. In the texts I have read I have found about X & Gamma but what are L & (U)-Gamma? I also enountered that they have separated the...

Hallo ... I would like to know about the effect of the effective mass on the band structre of the materails..

Hi again, first of all i want to thanks the replies to my previous posts. Second... I'm looking for a paper about the GaP band structure. Actually i only need the band structure tu compare it with mine but i need the reference to that paper, can you help me?? sorry for my bad english by the way...

First post,a good begin. As far as I know,the band gap is generated from the bragg reflection at the BZ boundary.So I think we just need the special K-point at the surface of 1BZ,and also the band gap(direct or indirect) is at the special K-point on the surface. But it seems not real in most...

I am trying to calculate a photonic crystal’s band structure for a very simply case of a 1-dimentional periodic medium, or rather I am trying to understand the calculations that I am looking at for this situation. The end result of what I would like to do is get some function that I can graph...

Hi, my name is Hans Lindroth and I have difficulties understanding how to determine the band structure of a chemical substance (in this case rhodamine B) experimentally, given I have the absorption spectrum of it. Is there anybody out there who can help me with this? If you can please help...

-Let's suppose we have 2 gases ..one is a "Fermi" gas under an Harmonic potential and the other is a "Bose" gas under another Harmonic potential... in both cases (as an approximation) the particles (bosons and electrons are Non-interacting) then we could write the partition functions. \prod...

for a ferromagnetic metal, the there will be splitting of energy band(one for spin up e- and one for spin down e-) under the influence of external magnetic field. the it is known as exchange splitting. here are my questions 1. what determine the degree of splitting? i guess it depends on the...

Consider a nucleus with N neutrons and Z protons. Can one justify it alternatively as a nucleus with N + Z protons and N electrons, the latter occupying orbitals either confined to the nucleus or following beta decay according to their electronic potential?

Dear all: I've been tortrued by this problem for a long time, please help me as possible as you can. 1. I want to know, after one get a dispersion picture of E(k), how to judge one of those curves stems from, say, px/py/pz sigma/pi (bond?)? That is to say, how to judge the curve's...

Please, help me to calculate the band structure of Si using the pseudopotential method. I will appreciate if you send me a simple program of calculation in any programming language very much and will be very grateful for any link or reference. The problem is than I've read the pile of books and...

Experiments to describe the band structure of bulk (solid) materials? I just want to know the name of some of the most used techniques to describe or obtain information of how the band structure of the material is. Not by theorethical calculations, just experiments. For example, let say I...