Debye Screening & Plasma Oscillations

Mobile electrons screen a test charge exponentially over the Debye length λ_D, and collective oscillations occur at the plasma frequency ω_p.

Density n: Temperature:

λ_D = 0.00 | ω_p = 0.00 | N_D = 0

Debye length: λ_D = √(ε₀k_BT / ne²). Plasma frequency: ω_p = √(ne²/ε₀m). The Debye sphere contains N_D = (4/3)πn·λ_D³ particles — plasma is only collective when N_D ≫ 1.