We introduce a one-dimensional spin injection structure comprising a ferromagnetic metal and a nondegenerate organic semiconductor to model electric current polarizations. With this model we analyse spin Coulomb dragg...We introduce a one-dimensional spin injection structure comprising a ferromagnetic metal and a nondegenerate organic semiconductor to model electric current polarizations. With this model we analyse spin Coulomb dragging （SCD） effects on the polarization under various electric fields, interface and conductivity conditions. The results show that the SCD inhibits the current polarization. Thus the SCD inhibition should be well considered for accurate evaluation of current polarization in the design of organic spin devices.展开更多
We report the formation energies of wurtzite zinc oxide （w-ZnO） nanowires （NWs） and nanotubes （NTs） with faceted morphologies, and show that hexagonal NWs （h-NWs） are energetically advantageous over the NWs wi...We report the formation energies of wurtzite zinc oxide （w-ZnO） nanowires （NWs） and nanotubes （NTs） with faceted morphologies, and show that hexagonal NWs （h-NWs） are energetically advantageous over the NWs with rhombic （r-）, squared （s-）, and triangular （t-） cross sections. The formation energies of h-NWs are proportional to the inverse of wire radius, whereas those of single-crystalline NTs are proportional to the inverse of wall thickness, irrespectively to tube radius. A simple model is presented to interpret these features.展开更多
基金Supported by the Natural Science Foundation of Shandong Province under Grant No Y2006A18, and the Key Programme of Natural Foundation of Shandong Jianzhu University under Grant No XZ050102.
文摘We introduce a one-dimensional spin injection structure comprising a ferromagnetic metal and a nondegenerate organic semiconductor to model electric current polarizations. With this model we analyse spin Coulomb dragging （SCD） effects on the polarization under various electric fields, interface and conductivity conditions. The results show that the SCD inhibits the current polarization. Thus the SCD inhibition should be well considered for accurate evaluation of current polarization in the design of organic spin devices.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10974119 and 10675075, the National Basic Research Program of China under Grant No 2005CB623602, and the Research Fund for Young Scientists in Shandong Province under Grant No 2006BSB01447.
文摘We report the formation energies of wurtzite zinc oxide （w-ZnO） nanowires （NWs） and nanotubes （NTs） with faceted morphologies, and show that hexagonal NWs （h-NWs） are energetically advantageous over the NWs with rhombic （r-）, squared （s-）, and triangular （t-） cross sections. The formation energies of h-NWs are proportional to the inverse of wire radius, whereas those of single-crystalline NTs are proportional to the inverse of wall thickness, irrespectively to tube radius. A simple model is presented to interpret these features.
