Tunneling spectroscopy as a probe of fractionalization in two-dimensional magnetic heterostructures

In this paper we develop the theory for two-dimensional to two-dimensional tunneling spectroscopy aided by magnetic or quantum-order excitations, and apply it to the description of van der Waals heterostructures of graphene or ultrathin alpha-RuCl3. We study the behavior of both the differential conductance and the inelastic electron tunneling spectrum (IETS) of these heterostructures. The LETS in particular exhibits features such as the gap of continuum spinon excitations and Majorana bound states, the energies of which scale cubicly with the applied magnetic field. Such scaling, which exists for a relatively wide range of fields, is at odds with the linear one exhibited by conventional magnons and can be used to prove the existence of Kitaev quantum spin liquids.