What does the Seebeck coefficient measure in a thermoelectric device?

In a thermoelectric device, the Seebeck coefficient ($\alpha$) serves as a proportionality factor that measures the relationship between a generated voltage and a temperature differential.12

Specifically, when a temperature difference ($\Delta T$) exists between the junctions of two dissimilar electrically conducting materials, it induces an electric potential difference. The resulting Seebeck voltage ($V_{\alpha }$) is defined by the equation:

$$V_{\alpha }=\alpha \Delta T$$

In this context, the Seebeck coefficient quantifies the magnitude of the voltage produced per unit of temperature difference. The value of $\alpha$ is dependent on the specific types of materials used at the junction. In the development of efficient thermoelectric power generators, the Seebeck coefficient is a critical parameter; it is a primary component of the "figure of merit," which helps determine the suitability of semiconductor materials for converting thermal energy into electric power.21