ZnO Semiconductor Nanostructures: Fabrication and Optimization of Photonic and Optoelectronic Properties

G. GRINBLAT; N.C. VEGA; D. COMEDI; A.V. BRAGAS

Workshop; Discussions on Nano & Mesoscopic Optics; 2015

The photonic properties of nanosized semiconductors are largely determined by surface effects, size, and morphology, and hence much effort has been directed recently to study and engineer these characteristics. The case of the ZnO nanostructure is particularly interesting due to its high exciton binding energy (60 meV), direct large bandgap (3.3 eV), and non-linear optics properties; and therefore it is very promising for applications in optoelectronic devices, such as ultraviolet laser diodes, solar cells, ultrasensitive gas sensors and many others [1]. Although ZnO and other nanostructures have been shown to grow easily, the control of their specific (surface and core) optoelectronic properties and the production of devices with high efficiency of light generation have proven difficult.This work focuses on the quest for a proper understanding and control of the relation between ZnO nanostructure growth processes, structure, and resulting optoelectronic properties [2], as well as the combination of ZnO nanoobjects with suitable plasmonic and other nanomaterials for the optimization of their linear and non-linear photonic and optoelectronic properties.In this research, efficient tunable second harmonic emission in individual ZnO nanocombs has been achieved [3], as well as highly enhanced UV excitonic luminescence and greatly increased photoconductivity in individual ZnO/MgO core/shell nanowires (with respect to bare ZnO nanowires) [4, 5]. Also, a study of single hybrid ZnO nanowire/Au plasmonic nano-oligomer for high efficiency light frequency upconversion is presented [6]. The experimental results are contrasted with numerical simulations and theoretical models, showing very good agreement. Controlling optoelectronic characteristics and photonic-plasmonic coupling in ZnO based nanostructures should be very useful for the effective manipulation of the emission and optoelectronic properties of these very promising systems.[1] A.B. Djurisic, A.M.C. Ng, X.Y. Chen. Prog. Quant. Electron. 34, 191 (2010); [2] G. Grinblat, M.G. Capeluto, M. Tirado, et al. Appl. Phys. Lett. 100, 233116 (2012); [3] M.G. Capeluto, G. Grinblat, M. Tirado, et al. Opt. Exp. 22, 5341 (2014); [4] G. Grinblat, L.J. Borrero-González, L.A.O. Nunes, et al. Nanotechnology 25,035705 (2014); [5] G. Grinblat, F. Bern, J. B.-Quiquia, et al. Appl. Phys. Lett. 104, 103113 (2014); [6] G. Grinblat, M. Rahmani, E. Cortés, et al. Nano Lett. 14, 6660 (2014)