We report the electronic properties of the Yb 3 Rh 4 Sn 13 -type single crystalline Ca 3 Rh 4 Sn 13 by means of the electrical resistivity, Hall coefficient, Seebeck coefficient, thermal conductivity, as well as 119 Sn nuclear magnetic resonance (NMR) measurements. The negative sign of the Hall coefficient and Seebeck coefficient at low temperatures suggests that the n-type carriers dominate the electrical transport in Ca 3 Rh 4 Sn 13 , in contrast to the observations in Sr 3 Rh 4 Sn 13 which has a p-type conduction. Such a finding indicates a significant difference in the electronic features between these two stannides. Furthermore, we analyzed the temperature-dependent 119 Sn NMR spin-lattice relaxation rate for Ca 3 Rh 4 Sn 13 , (Sr 0.7 Ca 0.3 ) 3 Rh 4 Sn 13 , and Sr 3 Rh 4 Sn 13 to examine the change of the electronic Fermi-level density of states (DOS) in (Sr 1-x Ca x ) 3 Rh 4 Sn 13 . It indicates that the Sn 5s partial Fermi-level DOS enhances with increasing the Ca content, being consistent with the trend of the superconducting temperature. Since the total Fermi-level DOS usually obeys the same trend of the partial Fermi-level DOS, the NMR analysis provides microscopic evidence for the correlation between the electronic DOS and superconductivity of the (Sr 1-x Ca x ) 3 Rh 4 Sn 13 system.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Materials Chemistry