Why Is the Radius of a Fermi Sphere Given by \( k_F = (3 \pi^2 n)^{1/3} \)?

AI Thread Summary
The radius of a Fermi sphere, represented by \( k_F = (3 \pi^2 n)^{1/3} \), is derived from the relationship between electron concentration and momentum space in quantum mechanics. This formula arises from the integration of states in three dimensions, where \( n \) denotes the electron concentration. The derivation can be found in the referenced text on page 138 of Kittel's book. Understanding this relationship is crucial for grasping the behavior of free electrons in solids. The discussion highlights the importance of foundational concepts in solid-state physics.
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[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 page 138

Homework Equations


The Attempt at a Solution

 
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