Drift current is the current that is a result of an applied electric field.

Overview

The drift current is the net charge of all the charge carrier at the carrier drift velocity. The drift velocity is defined as

There are free electrons per cubic meter of this material, each with have an elementary charge .

Drift current density due to free electrons

While the current density due to holes is

The total drift current density is the sum of the two drift current densities.

Where the conductivity is

which is the generalized form of Ohm's law.

Where is the conductivity [1/Ωcm] and is the resistivity [Ωcm].