band

  1. J

    Energy of band of d-dimensional semiconductor when voltage V is applied across

    Let's say we have a one-dimensional semiconductor and I apply voltage V across it, I want to calculate the energy of a parabolic band, when a source and drain voltage is applied across it. I expect it to be $U = \Sigma_k \frac{\hbar^2 k^2}{2 m^*}f(k)$ where f(k) is the fermi function. When no...
  2. S

    Band gap of cerium fluoride

    Do anyone have an idea about the band gap of cerium fluoride? I read much about its preparation and properties but did not found any info. About its band gap. Is it a large band gap or short band gap material?
  3. N

    reciprocal lattice in connection with band theory

    I need details on this topic ,this is my assignment but my solid state physics is not so good,and don't know much about it but i have to do this assignment ,i have material on reciprocal lattice but for only including in assignment ,not for my understanding,so frankly, i directly need any...
  4. S

    Band gap

    ZnO is a semiconductor material that has a band gap of 310 kJ/mol. What is the longest wavelength of light, in nm, that will excite an electron from the valence band to the conductance band?
  5. G

    Why does the Fermi level of an insulator fall within the band gap?

    "Fermi level" is the term used to describe the top of the collection of electron energy levels at absolute zero temperature. Why does the Fermi level of an insulator fall within the band gap? There is no energy level in the band gap. See also here
  6. O

    Graphene,band opening

    Graphene is a wonder material with exotic properties. But, zero band gap in graphene hinders its application in logic devices. what are the factors responsible for bandgap opening in graphene? How band gap is opened by hetero atom doping and chemical modification in graphene?
  7. P

    Force/pressure exerted from rubber band

    If you stretch a rubber band around a pole, the band exerts a force onto the surface of the pole (F1 in figure 1). Is it possible to calculate this force if I know the force needed to stretch the rubber band to the same total length as the circumference of the pole? That is to say: 1. I know the...
  8. J

    Energy band diagram

    Hi everyone, Having problems with the calculations for this question, i can't fine the formula.Really hope someone can help out, all help appreciated. Draw the energy band diagrams,showingEc,Ev,Ef & Ei for the following,assuming all impurities are ionised. a)Intrinsic Silicon at 300K...
  9. H

    band gap in metals and insulators

    I have a new q,perhaps it may solve the problem, suppose the electronic sturcture of a solid that represents a two dimensional square lattice of divalent atoms can be discribed using nearly free electron model with a weak potential such that U<<h^2/4M(Pi^2)*(Pi/a)^2 *=multiply ^2=square where...
  10. H

    band gap in metals and insulators

    I have a new q,perhaps it may solve the problem, suppose the electronic sturcture of a solid that represents a two dimensional square lattice of divalent atoms can be discribed using nearly free electron model with a weak potential such that U<<h^2/4M(Pi^2)*(Pi/a)^2 *=multiply ^2=square where...
  11. S

    Rubber Band Problem

    Basically a small box was released with a rubber band. The box was held by a rubber band. The box was released on a flat wooden surface. The problem is: Create a equation that will solve for distance that the box travels after losing contact w/ the rubber band. Variables available for...