Effects of hydrostatic pressure on spin-lattice coupling in two-dimensional ferromagnetic Cr_2Ge_2Te_6

摘要

Spin-lattice coupling plays an important role in both formation and understanding of the magnetism in two-dimensional magnetic semiconductors (2DMS). In this paper, the steady pressure effects on the lattice structure, Raman resonances, and magnetization of a 2DMS Cr2Ge2Te6 have been studied by both experiments and first principles calculations. It is found that the bond length of Cr-Cr decreases, the angle of Cr-Te-Cr diverges from 90 degrees, and the Raman modes E-g(3) and A(g)(1) show an increase with the application of external pressure. Consequently, the magnetic phase transition temperature T-C decreases from 66.6 K to 60.6 K (similar to 9%) as the pressure increases from 0 to 1 GPa. These pressure effects not only confirm the existence of strong spin-lattice coupling but also reveal the detailed information about the lattice deformation effect on the magnetic properties in such 2DMS, which would be a benefit for the further understanding and manipulation of the magnetism in 2D materials. Published by AIP Publishing.