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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Fermi Energy Result
Fermi Energy
—
eV
Fermi Energy
—
J (joules)
Step-by-step breakdown
EF = (ℏ²/2me) · (3π²n)2/3
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Summary
Enter electron number density to compute Fermi energy using EF = (ℏ²/2m)(3π²n)^(2/3).
How it works
- The free-electron model treats conduction electrons as non-interacting particles in a box.
- Filling energy states from the bottom up (Pauli exclusion principle) at T = 0 K defines the Fermi level.
- 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