1. Band Structure Engineering of Thermoelectric Materials- GeTe Jing ZhiLiang Nov 4 2015

2. Content Introduction of project -Objective -Materials -Method -Tool

3. Objective Enhance Thermoelectric Materials Performance by increasing figure of merit: Power factor is mainly determined by electronic structure

4. Materials GeTe (Gemanium Telluride): Thermoelectric material Narrow band gap semiconductor Rhombohedral structure Rock-Salt Structure(~700K) Brillouin Zone for FCC : http://optiwave.com/optifdtd-manuals/fdtd-fcc-lattices-of-air-spheres-in-dielectric/

5. Method 2 phenomena: band convergence and resonant state 1. Pei, Y., et al., Convergence of electronic bands for high performance bulk thermoelectrics. Nature, 2011. 473(7345): p. 66-9. 2. Peng, H., et al., Electronic structure and transport properties of doped PbSe. Physical Review B, 2011. 84(12). Band convergence & Resonant stateIncrease of S and σ

6. Method Objective Enhance the phenomenon of Band Convergence and Resonant State Materials Doping Control parameter: 1. Type of dopant (Ba, In, Ca, Hg, Zn, etc.) 2. Dose Evaluate the doping effects Plot band structure and DOS

7. Tool VASP Calculate band structure and DOS for different dopants and different dosage ●INCAR ●POSCAR ●POTCAR ●KPOINTS