We conduct systematical cathodolumiuescence study on red-shift of near-band-edge emission energy in elastic bent ZnO nanowires with diameters within the exciton diffusion length (- 200 nm) in liquid nitrogen tempera...We conduct systematical cathodolumiuescence study on red-shift of near-band-edge emission energy in elastic bent ZnO nanowires with diameters within the exciton diffusion length (- 200 nm) in liquid nitrogen temperature (81 K). By charactering the emission spectra of the nanowires with different; local curvatures, we find a linear relationship between strain-gradient and the red-shift of near-band-edge emission photon energy, an elastic strain-gradient effect in semiconductor similar to the famous flexoelectric effect in liquid crystals. Our results provide a new route to understand the inhomogeneous strain effect on the energy bands and optical properties of semiconductors and should be useful for designing advanced nano-optoelectronic devices.展开更多
文摘We conduct systematical cathodolumiuescence study on red-shift of near-band-edge emission energy in elastic bent ZnO nanowires with diameters within the exciton diffusion length (- 200 nm) in liquid nitrogen temperature (81 K). By charactering the emission spectra of the nanowires with different; local curvatures, we find a linear relationship between strain-gradient and the red-shift of near-band-edge emission photon energy, an elastic strain-gradient effect in semiconductor similar to the famous flexoelectric effect in liquid crystals. Our results provide a new route to understand the inhomogeneous strain effect on the energy bands and optical properties of semiconductors and should be useful for designing advanced nano-optoelectronic devices.