Publication de Thierry Ouisse
L'article intitulé "Electronic structure of the surface states of the Zr3SnC2 MAX phase" a été publié dans Physical Review B.
Ici vous trouverez l'article de Thierry Ouisse :
"We synthesized cm-sized single crystals of the nanolamellar compound Zr3SnC2 and performed angle-resolved photoemission spectroscopy (ARPES). A challenging problem to be solved, when studying electronic structure with ARPES, is to differentiate the surface and bulk electronic bands. We found that just after cleavage, the ARPES signal of Zr3SnC2 is dominated by surface states with well-defined energy dispersions. The (1 × 1) periodicity and the very good match of the electronic structure measured by ARPES with the DFT predictions indicate the absence of surface reconstruction. Mechanical cleavage happens at the Sn-Zr plane boundary, and the ARPES results are consistent with a top surface divided into locally unaltered regions covered with Sn atoms and regions terminated with Zr atoms. We provide a thorough analysis of these surface state bands. Longer-lived surface states are attributed to the Sn-terminated areas. DFT indicates that the surface bands of the Sn-terminated surface do not only involve Sn p orbitals, but also d orbitals of the Zr atoms lying closest to the surface. The orbital nature of the surface bands is further ascertained by ARPES."
"We synthesized cm-sized single crystals of the nanolamellar compound Zr3SnC2 and performed angle-resolved photoemission spectroscopy (ARPES). A challenging problem to be solved, when studying electronic structure with ARPES, is to differentiate the surface and bulk electronic bands. We found that just after cleavage, the ARPES signal of Zr3SnC2 is dominated by surface states with well-defined energy dispersions. The (1 × 1) periodicity and the very good match of the electronic structure measured by ARPES with the DFT predictions indicate the absence of surface reconstruction. Mechanical cleavage happens at the Sn-Zr plane boundary, and the ARPES results are consistent with a top surface divided into locally unaltered regions covered with Sn atoms and regions terminated with Zr atoms. We provide a thorough analysis of these surface state bands. Longer-lived surface states are attributed to the Sn-terminated areas. DFT indicates that the surface bands of the Sn-terminated surface do not only involve Sn p orbitals, but also d orbitals of the Zr atoms lying closest to the surface. The orbital nature of the surface bands is further ascertained by ARPES."