We use convincing experimental evidences to demonstrate that the nonpolar resistive switching phenomenon observed in Cu /ZrO2 :Cu /Pt memory devices conforms to a filament formation and annihilation mechanism. Temperature-dependent switching characteristics show that a metallic filamentary channel is responsible for the low resistance state "ON state#. Further analysis reveals that the physical...

The surface electronic structure of Ge(001) was studied by scanning tunneling spectroscopy. The measured surface densities of states unequivocally reveal the presence of a metallic state on the (2 x 1) domains, which is absent on the c(4 x 2) domains. This metallic state, so far observed only in integral measurements, is attributed to the flip-flopping dimers that constitute the (2 x 1) domains...

Local density approximation plus on-site Coulomb interaction U band structure calculations reveal that SrRuO3 exhibits a half-metallic ground state with an integer spin moment of 2.0 microB/SrRuO3. An associated tilting 4dt2g orbital ordering on a Ru sublattice is observed under the on-site Coulomb interaction U in the presence of lattice distortion. This finding unravels the on-site Coulomb co...