Thermoelectric effect in a bi-layer system

We show that an electric field appears in one layer of a bi-layer semiconductor system when a temperature gradient is applied in the other one. This trans-layer Seebeck effect exists on account of the inter-layer long-range electron–electron scattering and represents a generalization of the Coulomb drag phenomenon, defined as the mutual friction of two electron systems, to thermal perturbations. An effective thermopower coefficient αDαD is calculated within the random-phase approximation for the Coulomb interaction. At low temperature, αDαD is found to be directly proportional to the electron–electron scattering rate in 2D, τee−1.

► An electric field is induced by a temperature gradient in a bi-layer system.
► The origin of this effect is the Coulomb drag between the electrons in the layers.
► The magnitude of the effect is proportional to the electron relaxation rate.