Fermi Energy Calculator

Enter electron number density to compute Fermi energy using EF = (ℏ²/2m)(3π²n)^(2/3).

Electron Number Density

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m⁻³

Free-electron number density (m⁻³). Use scientific notation: 8.49e28

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Summary

Enter electron number density to compute Fermi energy using EF = (ℏ²/2m)(3π²n)^(2/3).

How it works

  1. The free-electron model treats conduction electrons as non-interacting particles in a box.
  2. Filling energy states from the bottom up (Pauli exclusion principle) at T = 0 K defines the Fermi level.
  3. Evaluating the Fermi wavevector kF = (3π²n)^(1/3) gives EF = ℏ²kF²/2mₑ.

Use cases

  • Verify textbook Fermi energy values for common metals like copper or aluminum.
  • Compute Fermi energy for custom electron densities in condensed matter research.
  • Check intermediate steps when learning solid-state physics derivations.
  • Compare Fermi energies across different materials by entering their free-electron densities.

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu