Thermoelectric Voltage Between Identical Metals in a Point-Contact Configuration

In an electric circuit made from only one metal with a thermal gradient over a point contact in the chain, thermoelectric voltages emerge as a result of the finite size of the contact. The phenomenon is described in terms of the difference in the transport properties of a point contact and the bulk, yielding the phonon drag as a major contribution to the measured thermopower at temperatures $T<\mathrm{}\frac{{\theta }_{\mathrm{D}}}{2}$.