The Drude model describes classical charge carriers accelerated by an applied electric field and randomized by collisions of constant mean waiting time . Its mean drift obeys , and harmonic conductivity is in the negative-frequency exponential convention.
The Drude model relative permittivity is . At frequencies large compared with the collision rate but below , its leading real part is negative and the physical spatial wave-number branch has positive imaginary part. The field therefore decays into the conductor; close to the threshold the full complex response must be retained.
Articles by others on the same topic
The Drude model is a classical model that describes the electrical and thermal properties of metals. Developed by physicist Paul Drude in 1900, this model treats conduction electrons in a metal as a gas of free, non-interacting particles. It provides a simple framework for understanding how electrical conductivity arises in metals and is foundational in solid-state physics.