scholarly journals Optical properties of free-standing GaAs semiconductor nanowires and their dependence on the growth direction

2008 ◽  
Vol 77 (7) ◽  
Author(s):  
P. Redliński ◽  
F. M. Peeters
Keyword(s):  
Optical Properties ◽  
Growth Direction ◽  
Semiconductor Nanowires ◽  
Free Standing

scholarly journals Free-Standing Si and Ge, and Ge/Si Core-Shell Semiconductor Nanowires

2012 ◽  
Vol 122 (2) ◽  
pp. 294-298 ◽  
Author(s):  
H. Peelaers ◽  
B. Partoens ◽  
F.M. Peeters
Keyword(s):  
Semiconductor Nanowires ◽  
Core Shell ◽  
Free Standing

Influence of Spontaneous and Piezoelectric Polarizations on the Lattice Dynamics of III-Nitride Structures

2001 ◽  
Vol 680 ◽  
Author(s):  
Jérôme Gleize ◽  
Jean Frandon ◽  
Marie A. Renucci ◽  
Friedhelm Bechstedt
Keyword(s):  
Elasticity Theory ◽  
Lattice Dynamics ◽  
Effective Strain ◽  
Growth Direction ◽  
Stress And Strain ◽  
Free Standing ◽  
The Difference ◽  
Piezoelectric Fields ◽  
Nitride Layers ◽  
Theory Framework

ABSTRACTThe influence of pyroelectric and piezoelectric polarizations on the lattice dynamics of strained III-nitride based structures is investigated within a macroscopic framework. New relationships between stress and strain are derived, which take into account the piezoelectric fields, which appear in the strained III-nitride layers. Consequently, the strained phonon frequencies in such systems differ from those calculated within the elasticity theory framework. In the case of strained, free-standing GaN/AlN superlattices grown along the [0001] axis, the difference of the spontaneous polarizations of GaN and AlN also contributes to the change in the effective strain along the growth direction. The corresponding shift of the zone center phonon frequencies of GaN and AlN might be negligible or significant, depending on the value of the ratio of the GaN and AlN layer thickness.

Tip-Induced Charging of Free Standing Semiconductor Nanowires and Carbon Nanotubes

2012 ◽  
Vol 52 (11-12) ◽  
pp. 1073-1080
Author(s):  
Sebastian Schäfer ◽  
Zhe Wang ◽  
Holger U. Rammelberg ◽  
Tobias Kipp ◽  
Alf Mews
Keyword(s):  
Carbon Nanotubes ◽  
Semiconductor Nanowires ◽  
Free Standing

Electronic and optical properties of free-standing and supported vanadium nanowires

2012 ◽  
Vol 111 (9) ◽  
pp. 093506 ◽  
Author(s):  
Poorva Singh ◽  
Tashi Nautiyal ◽  
Sushil Auluck
Keyword(s):  
Optical Properties ◽  
Free Standing ◽  
Electronic And Optical Properties

scholarly journals Hydrothermal Synthesis, Characterization, and Optical Properties of Ce Doped Bi2MoO6Nanoplates

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Anukorn Phuruangrat ◽  
Nuengruethai Ekthammathat ◽  
Budsabong Kuntalue ◽  
Phattranit Dumrongrojthanath ◽  
Somchai Thongtem ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Optical Properties ◽  
Photoelectron Spectroscopy ◽  
Hydrothermal Reaction ◽  
Growth Direction ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Uv Visible ◽  
Bending Modes

Undoped and Ce doped Bi2MoO6samples were synthesized by hydrothermal reaction at 180°C for 20 h. Phase, morphology, atomic vibration, and optical properties were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and UV-visible spectroscopy. In this research, the products were orthorhombic Bi2MoO6nanoplates with the growth direction along the [0b0], including the asymmetric and symmetric stretching and bending modes of Bi–O and Mo–O. Undoped and Ce doped Bi2MoO6samples show a strong absorption in the UV region.

Formation of Multiple Twinned Structural Units in Electrodeposited Nickel after Annealing

2014 ◽  
Vol 783-786 ◽  
pp. 2573-2578 ◽  
Author(s):  
Alexander Kahrimanidis ◽  
Uta Klement
Keyword(s):  
Grain Growth ◽  
Growth Direction ◽  
Zone Axis ◽  
Organic Additives ◽  
Free Standing ◽  
Structural Units ◽  
Ni Alloys ◽  
Orientation Change ◽  
Control Film ◽  
Electrodeposited Nickel

Electrodeposition is an advanced synthesis technique which involves the creation of a coating or free-standing material through an electrolytic process. Organic additives such as saccharin have been frequently used in electroplating operations to moderate deposit growth rates and to control film quality. In the present study, plating of Nickel without additives has resulted in a sub-microcrystalline microstructure and a <110>-fibre texture in growth direction. Structural units in form of groups of grains possessing a common <110>-zone axis in growth direction and low-Σ relationships between them have been found in the microstructure by use of EBSD. Upon annealing, grain growth sets in. However, the structural units and the texture are preserved up to 550°C. This means that the structural units stabilize the microstructure; there is no orientation change when grain growth occurs (e.g. by twinning). The low-Σ boundaries of the structural units are described in detail and texture development upon annealing is discussed in connection with results from previous studies on Ni and Ni-alloys of different initial texture.

Influence of reaction parameters on the photoluminescence properties of free standing functionalized silicon nanocrystals

2010 ◽  
Vol 1260 ◽  
Author(s):  
Anoop Gupta ◽  
Hartmut Wiggers
Keyword(s):  
Optical Properties ◽  
Surface Functionalization ◽  
Silicon Nanocrystals ◽  
Organic Molecules ◽  
Surface Passivation ◽  
Light Emission ◽  
Emission Spectra ◽  
Surface Oxidation ◽  
Free Standing ◽  
The Stability

AbstractWhile silicon nanostructures acquire novel optical properties due to miniaturization, the stability of light emission is severely limited because of exciton trapping due to surface oxidation coming along with the formation of defects. Grafting of organic molecules on a hydrogen-terminated silicon surface via hydrosilylation provides a promising route to stabilize their surface against oxidation. In this communication, we report on the effect of surface passivation on the optical properties of freestanding silicon nanocrystals (Si-NCs). The surface functionalization of hydrogen-terminated Si-NCs with organic molecules was achieved via liquid phase hydrosilylation. We demonstrate that surface functionalization does not preserve the original emission of hydrogen-terminated Si-NCs. It is observed that the emission spectrum of green emitting hydrogen-terminated Si-NCs is red shifted after surface functionalization. We find that the direction of shift does not depend on the type of organic ligands and the reaction conditions, however, the amount of shift can be altered. The factors influencing the shift in the emission spectra of functionalized Si-NCs with respect to hydrogen-terminated samples are discussed.

Optical properties and carrier dynamics of ensembles of InP nanowires grown on non-single-crystal platforms

2009 ◽  
Vol 1178 ◽  
Author(s):  
Takehiro Onishi ◽  
Andrew J. Lohn ◽  
Nobuhiko P. Kobayashi
Keyword(s):  
Optical Properties ◽  
Single Crystal ◽  
Quartz Substrate ◽  
Chemical Vapor ◽  
Blue Shift ◽  
Growth Direction ◽  
Longitudinal Optical ◽  
Face Centered Cubic ◽  
Single Crystal Surfaces ◽  
Face Centered

AbstractOptically active InP nanowires were grown on a quartz substrate covered with a layer (100 nm) of hydrogenated amorphous silicon (a-Si:H) by metalorganic chemical vapor deposition (MOCVD), demonstrating that single-crystal semiconductor nanowires can be formed on non-single-crystal surfaces. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, cathodoluminescence (CL), and photoluminescence (PL) were used to characterize the structural and optical properties of the nanowires. The nanowires on a-Si:H grew in random directions with high density. The XRD suggests that nanowires having either hexagonal-close-packed or face-centered cubic lattices co-exist. The Raman spectrum shows peaks associated with transverse optical (TO) and longitudinal optical (LO) branches of InP. The CL intensity does not vary signi?cantly along the growth direction and appears to be originated from the entire structure of the nanowire when probed at various positions. The CL data suggests that recombination is slow enough to allow the carriers to diffuse the complete length of the nanowires (˜2 m in length) before recombining. The PL spectrum suggested the nanowire had a part that contributes to the observed blue shift while the other part had nearly bulk feature in their structure.

Sign in / Sign up

Export Citation Format

Share Document