Fermi sphere Definition and 9 Threads
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Relationship between k and E when deriving the density of states
Number of states in that volume of k-space, ##n(k)dk## is: $$n(k)dk = (\frac{L^3}{4 \pi^3}) \cdot 4 \pi k^2 dk = \frac{L^3}{\pi^2}dk$$. Then the notes state that by defintion, ##n(k)dk = n(E)dE##, and hence $$n(E)d(E) = \frac{L^3}{\pi^2}dk$$. I don't quite see why this is true - isn't it the...- TIF141
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- Density Density of states deriving Fermi sphere Relationship States
- Replies: 1
- Forum: Introductory Physics Homework Help
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I Fermi sphere and density of states
Hello! When computing the density of states of electrons in a lattice, a material with dimensions L_x, L_y, L_z can be considered. The allowed \mathbf{k} vectors will have components k_x = \displaystyle \frac{\pi}{L_x}p k_y = \displaystyle \frac{\pi}{L_y}q k_z = \displaystyle \frac{\pi}{L_z}r...- EmilyRuck
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- Density Density of states Electrons Fermi Fermi sphere Lattice Sphere States
- Replies: 13
- Forum: Atomic and Condensed Matter
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A Fermi energy Ef changes with applied electric field?
Hi people, I don't understand why when we apply the electric field to the metal Ef remains the same. Ef as translation energy of electrons remains the same but we accelerate the electrons with applied electric field so the translation energy increases too? In other hand according the formula...- Dimani4
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- Applied Current flow Density of states Electric Electric field Energy Fermi Fermi energy Fermi sphere Field
- Replies: 5
- Forum: Quantum Physics
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F.E.G. fermi sphere radius problem
Homework Statement Calculate the electron concentrations (# electrons/atom) needed for the fermi sphere to contact the zone faces (first bril. zone edges) in BCC and FCC structures. Homework Equations kf = (3*pi^2*n)^(1/3) where n is # electrons per atom. For cubic structures...- lordkelvin
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- Fermi Fermi sphere Radius Sphere
- Replies: 1
- Forum: Advanced Physics Homework Help
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What is the Radius of Fermi Sphere for a 2D metal?
Homework Statement Problem 9.2(B) from Kittel Solid State Physics. A two-dimensional metal has one atom of valence one in a simple rectangular primitive cell of a1 = 2Å and a2 = 4Å. Calculate the radius of the free electron Fermi sphere and draw this sphere to scale on the drawing of the...- misterpickle
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- Fermi Fermi sphere Radius Sphere
- Replies: 1
- Forum: Advanced Physics Homework Help
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Maybe because is Fermi sphere is centered in origin?
In the theory of superconductivity BCS theory is given eigen - problem -\frac{\hbar^2}{2m}(\Delta_{\vec{r}_1}+\Delta_{\vec{r}_2})\psi(\vec{r}_1-\vec{r}_1)=(E+2\frac{\hbar^2k^2_F}{2m})\psi(\vec{r}_1-\vec{r}_1) Why E+2\frac{\hbar^2k^2_F}{2m}? Maybe because is Fermi sphere is centered in...- Petar Mali
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- Fermi Fermi sphere Origin Sphere
- Replies: 4
- Forum: Atomic and Condensed Matter
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Understanding Fermi Sphere: Deriving Fermi Energy
Hi all, I'm studying on the current transfer at quantum level and I have a point that is not so much clear. While reading the Fermi sphere from the book "Current at the nanoscale", I could not understand the expression: The number of electrons in the conductor, N, is the ratio of the...- carbon9
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- deriving Energy Fermi Fermi energy Fermi sphere Sphere
- Replies: 2
- Forum: Atomic and Condensed Matter
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Why Is the Radius of a Fermi Sphere Given by \( k_F = (3 \pi^2 n)^{1/3} \)?
[SOLVED] radius of the fermi sphere Homework Statement On page 249 of ISSP, Kittel says that the radius of a free electron Fermi sphere is k_F = \left(3 \pi^2 n \right)^{1/3} where n is the concentration of electrons. I don't know why that is true. EDIT: never mind; they derive that on...- ehrenfest
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- Fermi Fermi sphere Radius Sphere
- Replies: 1
- Forum: Advanced Physics Homework Help
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Relaxation time = displacement lifetime of fermi sphere?
Homework Statement I just want to clear this up, I am a little confused: when an electric field is applied there is a force on the electron K-states thus displacing the fermi surface/sphere Is the relaxation time ( \tau)= lifetime of fermi sphere displacement or is lifetime of...- neu
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- Displacement Fermi Fermi sphere Lifetime Relaxation time Sphere Time
- Replies: 1
- Forum: Advanced Physics Homework Help