Magnetism and magneto-transport in the chiral helimagnet Cr$_{\mathrm{1/3}}$NbS$_{\mathrm{2}}$: Microscopic insights from angle-resolved photoemission and time-resolved optical spectroscopy

The recent discovery of the soliton lattice, and the intriguing interplay between magnetic and transport degrees of freedom, make the chiral helimagnet Cr1/3NbS2 a very promising material both for technological applications, and for elucidating the connection between non-trivial spin textures and the microscopic interactions allowed in a crystalline lattice lacking in inversion symmetry. In this talk, we present recent results of photoemission and time-resolved optical spectroscopy on Cr1/3NbS2. Most notably, the data reveal that the Fermi surface is partially composed of Cr states, and that such states may give rise to a possible half metallicity as suggested by the characteristically long demagnetization dynamic measured from time-resolved magneto-optical Kerr effect (MOKE). Finally, it will be discussed how these findings are inconsistent with a description of magnetism and magnetotransport in this material based solely on spin ordering arguments.