Polarization Anisotropy, Frequency Dependent Emission, and Transport Properties of Dielectrophoretically Aligned CdSe Nanowire Arrays

Positive AC dielectrophoresis (DEP) is used to align ensembles of CdSe nanowires (NWs) near patterned micro-electrodes. Such wires, with the same crystal structure as CdSe quantum dots (QDs) and nanorods (NRs) but with significantly larger aspect ratios and sizable induced and intrinsic dipole moments, have a DEP mobility 10~100 times higher than other materials of the same dimension. As a consequence, they rapidly selfassemble in an AC electric field. The alignment also affects the fluorescence properties of the nanowires, revealing a high degree of polarization anisotropy in both the absorption and emission. An unexpected outcome of our work is the reversible, factor of