Some time ago we reported Co_1/3NbS₂ being the first magnetically intercalated transition metal dichalcogenide (TMD) where the magnetic ordering can be tuned by pressure to its full suppression [1]. Here we present the extended experimental and theoretical study that explores various implications of the interaction between metallic and magnetic layers [2]. New experimental investigations include neutron scattering experiments, ac and dc magnetic susceptibility measurements, and electrical transport measurements in the wide temperature and pressure ranges, resulting in the new phase diagram for Co_1/3NbS₂. The theoretical work focuses on revealing the mechanisms of magnetic ordering and its suppression under pressure, starting from calculations of electronic structure and magnetic interactions.  We conclude that magnetic couplings beyond nearest-neighbor in-plane interactions determine the nature of magnetic ordering. The suppression of ordering under pressure is ascribed to the shift in balance between super-exchange and RKKY magnetic couplings, leading to fully frustrated magnetic system.

[1] N. Barišić, I. Smiljanić, P. Popčević, A. Bilušić, E.Tutiš, A. Smontara, H. Berger, J. Jacimović, O.Yuli, L. Forró, Phys. Rev. B 84 (2011), 7; 075157

[2] Electronic transport and magnetism in the alternating stack of metallic and highly frustrated magnetic layers in Co_1/3NbS₂, P. Popčević, I. Batistić, A. Smontara, K. Velebit, J. Jaćimović, E. Martino, I. Živković, N. Tsyrulin, J. Piatek, H. Berger, A. Sidorenko, H. Rønnow, N. Barišić, L. Forró, and E. Tutiš, in preparation