Mr
GUY LEBA KABONGO
(University of South Africa)
05/05/2015, 09:10
SACPM
Oral Presentations
Mr
Jose Carvalho
(University of Sao Paulo)
05/05/2015, 09:30
SACPM
Oral Presentations
1. Introduction
The optical properties of zirconia materials have received much attention though no outstanding applications have been established so far. The advantage of combining the efficient luminescence of the trivalent rare earths (R3+) and the stable and versatile zirconia host has finally been ruined by the incompatibility of these two systems: the charge compensation defects created...
Prof.
Per Olof Holtz
(Linköping University, Sweden)
05/05/2015, 09:50
SACPM
Oral Presentations
1.Introduction
Polarized light is the basis for a manifold of optoelectronic technologies ranging from telecommunication and LCD-displays to quantum cryptography. However, it is challenging to efficiently attain a strong polarization of spontaneously emitted light, in particular for the generation of single photons. In solutions of today, mainly filtering of unpolarized light is employed. In...
Dr
Mmantsae Diale
(University of Pretoria)
05/05/2015, 10:10
SACPM
Poster Presentations
In this study, Au/Ni Schottky barrier contacts have been fabricated on AlGaN grown by hydride vapor-phase epitaxy (HVPE). After ohmic and Schottky contacts fabrication, the contacts were annealed at 500°C. The electrical characteristics of the diodes were investigated by using current-voltage measurements. The results show that the diodes characteristics improved after annealing, with reverse...
Dr
Lehlohonolo Koao
(UFS (Qwa Qwa))
05/05/2015, 11:40
SACPM
Oral Presentations
The X-ray diffraction results showed that All the ZnO samples possess a typical wurtzite structure for non-annealed and annealed. It was observed that the XRD diffraction intensities decrease with annealing temperature as shown in Fig. 1. This behaviour may be due the estimated crystallite size that decreased with annealing temperature. In Fig. 2 The XRD spectra of the annealed ZnO:Ce3+...
Prof.
Mike Lee
(NMMU)
05/05/2015, 12:00
SACPM
Oral Presentations
M.E. Lee1, J.H. O’Connell1, M.Y.A. Yagoub2, H.C. Swart2 and E. Coetsee2
1Centre for HRTEM, Nelson Mandela Metropolitan University, Port Elizabeth, 2Department of Physics, University of the Free State, Bloemfontein, South Africa
Corresponding author e-mail address: michael.lee@nmmu.ac.za
1. Introduction
Strontium fluoride (SrF2) is one of the most widely used optical materials due...
Prof.
Erik Janzen
(Semiconductor Materials (IFM), Linkoping University)
05/05/2015, 14:00
SACPM
Oral Presentations
SiC has during the last few years become increasingly important as a power-device material for high voltages. The thick low-doped voltage-supporting epitaxial layer is normally grown by CVD on 4˚ off-cut 4H-SiC substrates at a growth rate of 5-10 µm/h using silane and propane (or ethylene) as precursors. The concentrations of epitaxial defects and dislocations depend to a large extent on the...
Mr
Ezekiel Omotoso
(University of Pretoria)
05/05/2015, 14:20
SACPM
Oral Presentations
We have investigated the effect of 251-Am alpha-particle irradiation of energy 5.4 MeV on 1.9 × 10^(16) cm^(–3) N-doped 4H-SiC SBDs at different fluences. Prior to bombardment, we observed four defects with energies 0.10, 0.12, 0.16 and 0.65 eV below the conduction band. Alpha-particle irradiation introduced one additional defect with a very broad peak after receiving a 2.8 × 10^11 cm^(–2)...
Mr
Stive Roussel Tankio Djiokap
(Nelson Mandela Metropolitan University)
05/05/2015, 14:40
SACPM
Oral Presentations
Mr
Amos Akande
(Dept. of Physics, University of Limpopo, DST/CSIR National Centre for Nano-Structured Materials, P O Box 395, Pretoria 0001, South Africa)
06/05/2015, 11:20
SACPM
Oral Presentations
Vanadium dioxide (VO2) thermocromic properties have been widely applied in many devices in an attempt to solving the world energy crises. One of such devices is thermochromic/switchable/smart window, an energy saving window which is transparent to infrared light with high refractive index above 70 degree C (the transition temperature of VO2) and refracts infrared light with low refractive...
Dr
Daniel Wamwangi
(wits university)
06/05/2015, 11:40
SACPM
Oral Presentations
1. Introduction
Transition metal based thin films continue to attract tremendous research interest due to their excellent properties. As such they are widely used as protective coatings in optics and cutting tools due to their chemical properties, low wear and tear under extreme environments [1]. However delamination and intrinsic stress remain a great challenge especially in multilayer...
Dr
Zelalem N. URGESSA
(NMMU)
06/05/2015, 12:00
SACPM
Oral Presentations
Dr
Sergio Coelho
(UP)
07/05/2015, 09:40
SACPM
Oral Presentations
Dr
Vinod Kumar
(Department of Physics, University of the Free state, Bloemfontein, ZA-9300)
07/05/2015, 10:00
SACPM
Oral Presentations
1. Introduction
Zinc Oxide (ZnO) has attracted much attention in research activities with potential applications such as light emitting diode, spintronic device, transparent conductive electrodes, laser and solar cells due to its wide band gap (~3.37 eV) and large exciton binding energy (~60 meV) [1,2]. There are several deposition techniques used to grow ZnO thin films, including chemical...
Prof.
JAA Engelbrecht
(NMMU)
07/05/2015, 11:20
SACPM
Oral Presentations
1. Introduction
AlGaN alloys continue to be of great interest due to the application of these alloys in high-power, high-temperature and high-frequency devices such as field-effect transistors, UV-light emitting LED’s and laser diodes1-3. A range of different electrical and optical properties can be obtained by varying the alloy composition of AlxGa1-xN by changing the amount of Al in the...
Dr
Brahim Aissa
(QEERI-QF)
07/05/2015, 11:40
SACPM
Oral Presentations
We report on the incorporation of carbon nanomaterials (CNMs) such as single-walled carbon nanotubes (SWCNTs) into organic PV (OPV) cells for efficiency optimization. Although CNMs have been used before in OPVs, the focus is put here to elucidate the effect of the structural properties of the CNMs on OPV performance, which is poorly understood. More specifically, we address the issue of...
Prof.
Ernest van Dyk
(NMMU)
07/05/2015, 12:00
SACPM
Oral Presentations
1. Introduction
The performance and longevity of photovoltaic (PV) modules can be severely limited by poor material, manufacturing defects and physical cracks. Cell mismatch can occur when a solar cell in a series-connected string produces a lower current than the other cells in that string[1]. The current output of the entire string is limited by the weakest cell in the string so damage...
Prof.
Jorma Hölsä
(University of Turku)
07/05/2015, 13:30
SACPM
Oral Presentations
1. Introduction
Both the commercial markets as well as research and development of persistent luminescence phosphors have been dominated by materials doped with Eu2+. The domination of Eu2+ over other rare earths (R; e.g. Ce3+, Pr3+, Tb3+) is due to e.g. the strong and easily tunable emission (Fig. 1) as well as the favourable energy level scheme of Eu2+ vs. the host band structure [1]....
Mr
Abd Ellateef Abbass
(Sudanese)
07/05/2015, 13:50
SACPM
Oral Presentations
ZnO has attracted considerable attention as a photonic material and ZnO:Tb is a promising material for phosphor converted white light emitting diodes. It has been reported that metallic Ag nanoparticles will precipitate if an excessive amount of Ag is doped into ZnO and localized surface plasmon resonance effects associated with metallic nanoparticles are of great interest because they have...
Dr
Anurag Pandey
(University of the Free State)
07/05/2015, 14:10
SACPM
Oral Presentations
1. Introduction
Lanthanides activated luminescent materials having increasing interest among researchers owing to its broad area of applications in photonic, sensing, security and biomedical fields [1]. Rare earth doped glasses are one of the best luminescent solids because of their multifunctional uses from daily live to scientific applications. Tellurite glasses are a better choice for...
Mr
Kiplagat Ayabei
(University of the western cape)
07/05/2015, 14:30
SACPM
Oral Presentations
1. Introduction
In the recent past, magnetic materials and semiconductor inorganic materials have been developed and applied (as independent) in fields including biomedicine, especially biotechnological processes imaging, tracking, and separating biological molecules or cells. Processes of biomedical diagnosis and therapy require nanometer scale particles featuring characteristics such as...
Prof.
Hendrik Vissser
(University of the Free State)
07/05/2015, 15:20
SACPM
Oral Presentations
Metal quinolinates are known as key materials in the design of organic light emission diodes (OLEDs). The aluminium complex, tris-(8-hydroxyquinoline) aluminium(III), is the most well-known molecule of this family, although its gallium analogue has also been considered for use in OLEDs [1,2]. Factors that govern the efficacy these metal complexes for potential use in OLEDs include the type...
Dr
Mart-Mari Duvenhage
(University of the Free State)
07/05/2015, 15:40
SACPM
Oral Presentations
Although tris-(8-hydroxyquinoline) aluminium (Alq3) is used as a green emissive layer in organic light emitting diodes (OLED) it tends to degrade with time leading to a decrease in device performance and efficiency. It has been reported that by substituting Al with Zn to form bis-(8-hydroxyquinoline) zinc (Znq2), the Znq2 shows advantages over the Alq3 in electron transport and higher quantum...
Ms
WINFRED MULWA
(University of the Free State-Qwaqwa campus, Department of physics, Private Bag x13, Phuthaditjhaba, 9866, SOUTH AFRICA)
07/05/2015, 16:00
SACPM
Oral Presentations
In this study, plane wave self consistent field calculations have been performed on the electronic structure of rutile and anatase phases of titanium dioxide (TiO2). To this end ab-initio calculations have been performed for a 48-atom rutile supercell and 96-atom anatase supercell using the plane wave code – Quantum Espresso. Density functional theory (DFT) with hybrid functionals have been...
