Evidence of itinerant holes for long-range magnetic order in the tungsten diselenide semiconductor with vanadium dopants

Abstract

One primary concern in diluted magnetic semiconductors (DMSs) is how to establish a long-range magnetic order with low magnetic doping concentration to maintain the gate tunability of the host semiconductor, as well as to increase Curie temperature. Several van der Waals semiconductors have been investigated recently to demonstrate the magnetic order in DMSs. Nonetheless, a comprehensive understanding of the operative mechanism has remained elusive. Here, we demonstrate concrete evidence of the long-range magnetic order through itinerant spin-polarized holes in a monolayer V-doped $\mathrm{W}{\mathrm{Se}}_{2}$ semiconductor. Hybridization between V impurity states and the host valence band has been investigated using scanning tunneling microscopy. Transport characteristics reveal the itinerant holes within the hybridized band and hysteresis in magnetoresistance; this clearly resembles the Zener-type description of the itinerant ferromagnetism as predicted by density functional theory calculations.