Dead Magnetic Layers At The Interface: Moment Quenching Through Hybridization And Frustration

Using spin-polarized scanning tunneling microscopy (STM) we observe a two-dimensional c(2x2) antiferro-magnetic state in a pseudomorphic Mn double layer on the W(001) surface. First-principles calculations confirm the antiferromagnetic ground state. Surprisingly, only the surface Mn layer possesses a magnetic moment while the moments of interface Mn atoms vanish. Calculated STM and spin-polarized STM images as well as local vacuum density of states are in good agreement with experiments and provide strong evidence of a dead magnetic interface layer.