Physics
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Debye Length Calculator.
Calculate single-species plasma Debye length from temperature, number density, and charge magnitude.
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01
Set your values
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02 / ANSWER
Debye length: 0.000069 m
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