Debye Length - Debye Length in A Plasma

Debye Length in A Plasma

In a plasma, the background medium may be treated as the vacuum, and the Debye length is

where

λ_D is the Debye length,

ε₀ is the permittivity of free space,

k_B is the Boltzmann constant,

q_e is the charge of an electron,

T_e and T_i are the temperatures of the electrons and ions, respectively,

n_e is the density of electrons,

n_ij is the density of atomic species i, with positive ionic charge jq_e

The ion term is often dropped, giving

although this is only valid when the mobility of ions is negligible compared to the process's timescale.