Unraveling Four-Phonon Contributions to Thermoelectricity in Ba4Sb2Se and Ba4Sb2Te
We conduct a systematic study that couples first-principles lattice dynamics, including three- and four-phonon processes, with parameter-free electronic transport simulations to quantify the thermoelectric response of Ba4Sb2Se and Ba4Sb2Te. Four-phonon processes expand the anharmonic phase space and suppress the lattic...