Tunable density waves in Co-intercalated NbSe2

Charge density waves (CDWs) in the family of transition metal dichalcogenides have been of intense interest. Bulk 2H-NbSe2 hosts a well-known CDW phase (T_CDW ~ 33 K) that coexists with superconductivity at low temperature. Introducing magnetism to this already superconducting CDW material would be of high interest. For example, by depositing individual magnetic adatoms it has already been shown that this could have an effect on the overall appearance of the CDW [1]. Here, we analyze the interplay of this CDW and magnetism by studying Co-intercalated bulk single crystals of NbSe2 via scanning tunneling microscopy/spectroscopy (STM/S) and spin-polarized STM/S (SP-STM/S). We image the magnetic-field-evolution of the CDW phase and the density-of states, and we will discuss the implications of the magnetic field sensitivity of STM and SP-STM measurements. Our findings demonstrate the rich physics that comes about by intertwining magnetism with superconductivity and CDWs in NbSe2.

[1] Rutten, L. et. al., Charge-density-wave control by adatom manipulation and its effect on magnetic nanostructures, arXiv:2410.02018