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Debye Length Calculator.

Calculate single-species plasma Debye length from temperature, number density, and charge magnitude.

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Debye length: 0.000069 m

Debye length

0.000000m

Results update automatically as you type.

Use Cases

Plasma physics research

Determine the screening length in laboratory or astrophysical plasmas to understand collective behavior and wave propagation.

Example: Calculate Debye length for a plasma with T=10000 K, n=1e18 m⁻³, q=1.6e-19 C.

Educational demonstrations

Use in physics courses to illustrate how temperature and density affect electrostatic screening in plasmas.

Example: Show how increasing density reduces the Debye length.

Frequently Asked Questions

What is the Debye length?
The Debye length is the characteristic distance over which electric fields are screened in a plasma. It depends on the temperature, number density, and charge of the particles. This calculator computes it for a single-species plasma using the given inputs.
How is the Debye length calculated?
The Debye length is calculated using the formula: λ_D = sqrt(ε₀ * k_B * T / (n * q²)), where ε₀ is the vacuum permittivity, k_B is Boltzmann's constant, T is temperature in Kelvin, n is number density in m⁻³, and q is charge magnitude in Coulombs. This calculator applies that formula.
What units should I use for temperature, density, and charge?
Temperature must be in Kelvin (K), number density in particles per cubic meter (m⁻³), and charge magnitude in Coulombs (C). The calculator will output the Debye length in meters.

Tips & Common Mistakes

Tips

  • Ensure temperature is in Kelvin; convert from Celsius by adding 273.15.
  • Number density should be in particles per cubic meter; convert from cm⁻³ by multiplying by 1e6.
  • For electron plasmas, use the elementary charge (1.602e-19 C) as the charge magnitude.
  • Double-check that you are using the correct charge magnitude for the species (e.g., singly ionized vs. multiply charged).

Common Mistakes to Avoid

  • Using temperature in Celsius or Fahrenheit without converting to Kelvin.
  • Entering density in cm⁻³ instead of m⁻³, leading to results off by a factor of 1e6.
  • Forgetting to square the charge magnitude in the formula, which would give an incorrect Debye length.

Last updated: August 13, 2026