NMR study on CoSb3-based skutterudites
Filled skutterudite compounds MT4X12 (space group Im3), where M is the guest atoms such as Ba, Yb, etc., and T atom is Co, Rh, Ir, and X is the pnicogen atom (P, As, and Sb) have gained great attention due to their outstanding thermoelectric performance, superconductivity, magnetic ordering, unusual metal-insulator transitions, heavy fermion behaviors.
The filled skutterudites obey the phonon-glass electron-crystal concept in which the thermal conductivity reduces significantly. This observed first by Morelli et al. where the lattice thermal conductivity decreases due to loosely bonded Ce in the structure. Although the guest atoms substitution in binary skutterudites result in low thermal conductivity, the 4f states of them can bring flat band and lowers the mobility of carriers.
Yefan Tian et al., "NMR study of YbxCo4Sb12", Preparing (2019).
Yefan Tian, Ali A. Sirusi, Sedat Ballikaya, Nader Ghassemi, Ctirad Uher, and Joseph H. Ross, Jr., “Charge-carrier behavior in Ba-, Sr- and Yb-filled CoSb3: NMR and transport studies”, Phys. Rev. B 99, 125109 (2019).
Yefan Tian, Ali A. Sirusi, Sedat Ballikaya, Nader Ghassemi, Ctirad Uher, and Joseph H. Ross, Jr., “NMR investigation of filled skutterudites BaxYbyCo4Sb12 and AxCo4Sb12 (A = Ba, Sr)”, APS March Meeting 2019, Oral Presentation, R47.00008 (2019, Boston, MA).
Yefan Tian, Ali Sirusi, Joseph H. Ross, Jr., Sedat Ballikaya, Ctirad Uher, Yuqi Chen, and Chihiro Sekine, “NMR study of partially filled skutterudites AxCo4Sb12 (A = Yb, Ba, Sr, Ca) and BaxYbyCo4Sb12”, APS March Meeting 2017, Oral Presentation, Y36.00002 (2017, New Orleans, LA).