Multiple Magnon Excitation in NiO by Electron Tunneling

Abstract
We report our observation of magnon excitation in antiferromagnetic NiO by electron tunneling through single-crystal Ni-NiO-Pb junctions. We compare the derivative of the tunnel conductance of the junction with a realistic magnon density of states of NiO and show that the observed structures indeed reflect the one-magnon, two-magnon, and three-magnon density of states of NiO.