Wiedemann-Franz Law: Electron Gas Transport in a Metal

Conduction electrons in a metal carry both electric current and heat, and the Wiedemann–Franz law says the ratio of their thermal to electrical conductivity is a universal constant, the Lorenz number, set only by fundamental constants. This simulation renders a free electron gas drifting and scattering through a lattice of ion cores under a real Drude-model relaxation-time calculation, combining a chosen metal's electron density and Debye temperature with adjustable temperature, impurity level and applied field. Live readouts track electrical conductivity σ, thermal conductivity κ, the measured Lorenz ratio against its theoretical value, the scattering time τ and the electron mean free path, while the "How it works" panel explains the real electron-phonon deviation that makes the Lorenz ratio dip below its ideal value at intermediate temperature.