Refractive index dispersion deduced from lasing modes in ZnO microtetrapods

Abstract

High optical quality, well end leg faceted ZnO microtetrapods sustaining lasing modes with quality factors of 2500–3000 have been grown by carbothermal chemical vapor deposition. It is shown that lasing is due to longitudinal Fabry–Pérot modes in individual tetrapod legs and the analysis of the wavelength position of these modes is an effective instrument for the investigation of temperature dependence of the refractive index dispersion in the region of exciton resonances. The dispersion of the ZnO refractive index is experimentally determined in the temperature interval from 10 to 300 K and is compared with available literature data.

Polariton condensates at room temperature

“…While most works have been reported with planar microcavities, alternative optical resonators are also explored. The possibility of a self-organized growth of GaN and ZnO into hexagonal nanowires [43,67,68] and microwires [11,12,29,45,46,69] has led to interesting resonators which crystalline quality is improved compared to planar structures. The exciton then couples to either longitudinal Fabry-Perot modes in cleaved nanowires (like in a finite length monomode optical fiber), or whispering gallery modes in micron-thick wires.…”

Light–matter interaction and polarization of single ZnO nanowire lasers

“…[4][5][6] ZnO nanocrystals with an anisotropic one-dimensional shape are usually formed by gas-phase and solution methods because wurtzite ZnO has a natural polar axis of fast crystal growth. [7][8][9][10][11][12][13][14][15][16] The nanowires with the diameter range of 100 nm do not show electronic confinement, whereas the confinement of the electromagnetic waves maintains standingwave electromagnetic modes. These features lead to novel optical properties associated with the nanowire geometry in addition to the electronic states of ZnO.…”