Poster: Tuning the magnetic properties of CrI₃ using Ni

Chromium triiodide (CrI₃) has recently been demonstrated to host Ising ferromagnetism down to the monolayer limit. In this work, we use polarization-resolved magneto-Raman spectroscopy to probe the magnetic properties of CrI₃ crystals with nanometer thickness of Ni deposited on the surface. The deposited Ni thin layer forms nanoclusters that completely cover the CrI₃ surface. By comparing ultra-low frequency Raman spectra of spin-wave modes from pristine bulk CrI₃ and from bulk CrI₃ with a thin layer of Ni on the surface, we see that CrI₃ with Ni on the surface shows only a single spin wave branch at magnetic field up to 7 T, suggesting the existence of only a ferromagnetic phase. This is different from pristine CrI₃ whose spin wave spectra show three branches below 2T from a mixed state of antiferromagnetism on the surface and ferromagnetism in deeper bulk layers. Our studies show that the magnetic phase of CrI₃ can be controlled through the deposition of thin metal layers on the surface.