A multi-band refinement technique for analyzing electronic band structure of thermoelectric materials

Investigation of electronic band structure (EBS) plays a pivotal role in the advancement of thermoelectric materials and devices. Sophisticated experiments and theoretical calculations are required to obtain EBS information, representing a bottleneck in studying the vast and increasing number of thermoelectric materials. Herein, we propose a refinement-based approach, referred to as the multi-band refinement technique (MBRT), that combines routine laboratory measurements with computationally inexpensive calculations to acquire EBS information. Experimental data of electrical conductivity, Seebeck coefficient, and Hall coefficient along with an electronic transport model act as inputs. The MBRT solver uses this information to iteratively refine electronic structure and scattering parameters by a least-square minimization technique. The efficacy of the MBRT has been validated using silicon, an archetypal semiconductor, and Mg2Si, a well-known thermoelectric material. The results demonstrate that the MBRT can be a powerful tool for studying the effects of temperature, doping, and alloying on the EBS of thermoelectric materials.