Multiple charge density wave states and magnetism in NdPt2Si2 against the background of its nonmagnetic analog LaPt2Si2
Abstract
Results of structural, magnetic, thermodynamic, and electron transport measurements on single-crystalline NdPt2Si2 are reported. Temperature variations of crystal structure show two different charge density wave states.
The structure modulation with the propagation vector q(1) = (0.323, 0, 0) arises below T = 300 K. An additional modulation, with propagation vector q(2) = (0.163, 0.163, 0.500), appears below T = 50 K in a first-order phase transition.
This situation was found analogous to isostructural LaPt2Si2 with similar (but not identical) propagation vectors and characteristic temperatures. Nd magnetic moments order antiferromagnetically at T-N = 1.5 K.
Temperature dependence of electrical resistivity for current j applied along the a, b, and c axes is strongly affected by the first-order transition, inducing a Fermi surface gapping.