Fig. 3: Phonon transport properties and mechanism of (GeTe)1-x(CuBiS2)x samples.

a Total thermal conductivity (κT). b Lattice thermal conductivity (κL). c Calculated spectra lattice thermal conductivity (κs) by the Debye-Callaway model, with different phonon scattering mechanisms at 300 K. d Temperature dependent the calculated κL by the Debye-Callaway model includes different scattering mechanisms and is compared with the experimental values of the (GeTe)0.93(CuBiS2)0.07 sample.