Charge density wave in layered La1-xCexSb2

R. F. LUCCAS; A. FENTE; J. HANKO; A. CORREA-ORELLANA; E. HERRERA; E. CLIMENT-PASCUAL; J. AZPEITIA; T. PEREZ-CASTAÑEDA; M. R. OSORIO; E. SALAS-COLERA; N. M. NEMES; F. J. MOMPEAN; M. GARCÍA-HERNÁNDEZ; J. G. RODRIGO; M. A. RAMOS; I. GUILLAMÓN; S. VIEIRA; H. SUDEROW

Physical Review B

American Physical Society

Lugar: New York; Año: 2015 vol. 92 p. 235153 - 235153

The layered rare-earth diantimonides RSb2 are anisotropic metals with generally low electronic densities whose properties can be modified by substituting the rare earth. LaSb2 is a nonmagnetic metal with a low residual resistivity presenting a low-temperature magnetoresistance that does not saturate with the magnetic field. It has been proposed that the latter can be associated to a charge density wave (CDW), but no CDW has yet been found. Here we find a kink in the resistivity above room temperature in LaSb2 (at 355 K) and show that the kink becomes much more pronounced with substitution of La by Ce along the La1−xCexSb2 series. We find signatures of a CDW in x-ray scattering, specific heat, and scanning tunneling microscopy (STM) experiments in particular for x ≈ 0.5. We observe a distortion of rare-earth?Sb bonds lying in-plane of the tetragonal crystal using x-ray scattering, an anomaly in the specific heat at the same temperature as the kink in resistivity and charge modulations in STM. We conclude that LaSb2 has a CDW which is stabilized in the La1−xCexSb2 series due to substitutional disorder.