Optical characterization of wurtzite gallium nitride nanowires

Abstract

The optical properties of the gallium nitride (GaN) nanowires are examined by the transmission method in the ultraviolet-visible range (1–5 eV) and by the reflection method in the infrared range (500–4000 cm−1). The absorption edge of the GaN nanowires is blueshifted by 0.2 eV from the bulk edge. The temperature dependence of the energy gap is expressed by, Eg(T)=3.724−9.97×10−4/(861+T) eV. The plasma frequency and the free-carrier density of the GaN nanowires, deduced from the infrared reflectance minima, are estimated to be ωp=1100±120 cm−1 and nf=3.73×1017 cm−3, respectively. Obtaining the free-carrier density from the infrared reflectance spectra is especially useful in research on nanostructured semiconductors.

Silicon Carbide Nanosprings

“…One-dimensional nanowires are attracting increased attention from the scientific and technological communities because of their versatile electrical, optical, and mechanical properties. [1][2][3][4][5][6] Potential applications for these novel structures range from tips in scanning probe microscopes to interconnects in nanoelectrical devices as well as the utilization of their fieldemission properties in flat-panel displays. [7][8][9] Silicon carbide (SiC) is a particularly attractive material for these applications because of its high thermal and electric conductivities and outstanding mechanical properties.…”

“…One-dimensional nanowires are attracting increased attention from the scientific and technological communities because of their versatile electrical, optical, and mechanical properties. − Potential applications for these novel structures range from tips in scanning probe microscopes to interconnects in nanoelectrical devices as well as the utilization of their field-emission properties in flat-panel displays. − Silicon carbide (SiC) is a particularly attractive material for these applications because of its high thermal and electric conductivities and outstanding mechanical properties . Several groups have successfully synthesized SiC nanowires (or nanorods) by a variety of techniques. − For example, Dai et al prepared SiC nanorods through a reaction between carbon nanotubes and SiO or SiI 2 , and Meng and co-workers fabricated SiC nanorodes by the carbothermal reduction of sol−gel-derived silica xerogels containing carbon nanoparticles .…”

Photoluminescence and lasing characteristics of single nonpolar GaN microwires

“…13 The single crystalline GaN MW has been considered as one of the most promising materials for detecting UV spectrum because of its direct and suitable wide band gap and high absorption coefficient in the UV range. 14 Optical properties of GaN MWs have been extensively studied, including reectance and transmission in the UV-visible-infrared region, 15,16 photoluminescence (PL), [17][18][19][20] and Raman scattering spectroscopy. 17,[21][22][23] The quantum connement effect responsible for direct band-toband transition in the encapsulated one-dimensional MW has been observed.…”

10.1007/s11448-008-2010-8

“…For Group III nitrides, in particular for GaN, these studies are at the initial stage. Recently, the first results on the epitaxial growth of surface nanoobjects in the form of nanowires and pillars were presented [10,11].In this work, we present the data on the creation and analysis of a regular nanostructure of a new nanocomb type formed as a result of the self-organization processes induced by multiple co-adsorptions of the Cs and Ba atoms on the n-GaN surface. The nanostructure has been studied by the methods of AFM, electron microscopy, and photoemission spectroscopy.…”

“…For Group III nitrides, in particular for GaN, these studies are at the initial stage. Recently, the first results on the epitaxial growth of surface nanoobjects in the form of nanowires and pillars were presented [10,11].…”