Conveners
Photonics: Spectroscopy
- Tjaart Krüger (University of Pretoria)
Photonics: Lasers and Optics
- Pieter Neethling (Laser Research Institute, University of Stellenbosch)
Photonics: Beam Shaping & Meeting
- Andrew Forbes (U. Witwatersrand)
Photonics: Applied Photonics
- Carmelo Rosales-Guzman (University of the Witwatersrand, Johannesburg)
Photonics: Applied Photonics
- Bienvenu Ndagano (University of the Witwatersrand)
Photonics: Bio-Photonics
- Gurthwin Bosman (Stellenbosch University)
Mr
Wendall Coenraad
(Stellenbosch University)
27/06/2018, 10:00
Track C - Photonics
Oral Presentation
Optical Coherance Tomography (OCT) is an interferometric technique, which allows for non-invasive in vivo diagnostic medical imaging. It is a powerful tool in ophthalmology since it is able to produce high-resolution 2D profiles or 3D reconstructions of ocular structures to aide in the early diagnosis of ocular diseases. The main advantages associated with OCT are its high resolution and depth...
Mr
Brandon Hattingh
(University of Stellenbosch)
27/06/2018, 10:20
Track C - Photonics
Oral Presentation
Resonant Ionisation Spectroscopy (RIS) is a technique to selectively ionise a particular element or even isotope. It has applications in the production and quality assurance of isotopes for medical applications. It is also applied for the production and study of beams of exotic nuclei in large nuclear physics facilities such as CERN. We report on the development of a heat pipe based setup for...
Mr
George Okyere Dwapanyin
(Stellenbosch University)
27/06/2018, 10:40
Track C - Photonics
Oral Presentation
The quest to probe deeper into biological tissue has led to the development of many microscopic techniques ranging from the linear regime, such as bright-field microscopy, to higher order nonlinear optical microscopy (NLOM) techniques. These NLOM permit intrinsic 3D imaging with submicron spatial resolution, decreased photodamage to tissue, increased depth of penetration, as well as the...
Mr
jean jacques monga kaboko
(university of johannesburg)
27/06/2018, 11:20
Track C - Photonics
Oral Presentation
Stable and single-longitudinal-mode Erbium-doped fiber ring lasers (EDFRLs) have been studied intensively due to their wide range application in field like optical communication and fiber sensors. Because of the fiber vulnerability to perturbation of temperature and vibration, it has been demonstrated that the output power of the conventional fiber ring lasers are unstable. In this report, the...
Ms
Hend SROOR
(University of The Witwatersrand)
27/06/2018, 11:40
Track C - Photonics
Oral Presentation
Vector beams are spatial modes of light in which the polarization and spatial degree of freedom are inseparable. Such beams have widely been used in applications ranging from optical tapping and tweezers to optical communications. Yet, these vector beams have been only generated in low power due to limitation in the tools used to generate them. Here, we show the amplification of vector beams...
Mr
Jonathan Pinnell
(University of the Witwatersrand)
27/06/2018, 12:00
Track C - Photonics
Oral Presentation
Spontaneous parametric down-conversion (SPDC) has been (and continues to be) a very popular mechanism for generating entangled biphotons for applications in fields ranging from quantum key distribution and quantum computing to quantum imaging. In a nutshell, if ones impinges a crystal (characterised by a nonlinear, second-order susceptibility tensor) with a pump photon, there is a small...
Dr
Carmelo Rosales-Guzman
(University of the Witwatersrand, Johannesburg)
27/06/2018, 12:20
Track C - Photonics
Oral Presentation
It is well known that the entanglement of a quantum state is invariant under local unitary transfor- mations. It dictates, for example, that the degree of entanglement of a photon pair in a Bell state remains maximally entangled during propagation in free-space. Here we outline a scenario where this paradigm does not hold. Using local Bell states engineered from classical vector vortex beams...
Mr
Ravin Kara
(University of the Witwatersrand)
27/06/2018, 12:40
Track C - Photonics
Oral Presentation
Digital micro-mirror devices (DMDs) are composed of arrays of micro-mirrors that are able to reflect incident light in ways based on the binary operational state of each mirror. Traditionally used in digital light processing, its importance in research aspects has increased. The operational states of the mirrors make the DMD an amplitude-only light modulating device at high speeds, insensitive...
Mr
Mitchell Cox
(University of the Witwatersrand)
27/06/2018, 14:00
Track C - Photonics
Oral Presentation
The use of higher order modes in optical communications is topical due to their versatility and in particular their ability to conveniently increase the number of degrees of freedom in a communications system. This enables multiplexing for higher bandwidth communications as well as diversity for improving the robustness of a link. One of the main reasons why we do not see commercial systems...
Mr
NKOSIPHILE ANDILE BHEBHE
(UNIVERSITY OF THE WITWATERSRAND)
27/06/2018, 14:20
Track C - Photonics
Oral Presentation
Laser beams structured to have a uniform peak intensity profile (flat-top) have become ubiquitous and a topic of interest in many research fields. However, such beams alter their intensity profile as they propagate in free space. This problem can be overcome by generating vector flat-top beams. Here, we present theoretical simulations and demonstrate experimentally the creation of propagation...
Prof.
Andrew Forbes
(U. Witwatersrand)
27/06/2018, 15:40
Ms
Anneke Erasmus
(Stellenbosch University)
27/06/2018, 16:00
Track C - Photonics
Oral Presentation
Optical tweezers demonstrate how light can be applied to exert piconewton forces on a microscopic particle. This allows for the particle to be spatially manipulated in three dimensions. Optical tweezing is achieved by creating an optical trap. In this work, a single beam optical trap is created using a high numerical aperture microscope objective to focus a near infrared laser into a sample....
Mr
Bienvenu Ndagano
(University of the Witwatersrand)
27/06/2018, 16:20
Track C - Photonics
Oral Presentation
Quantum key distribution (QKD) allows the secure sharing of information by exploiting the laws of physics. Traditionally demonstrated with polarisation, there has been novel avenues of research whereby the spatial degree of freedom is employed to increase the bandwidth; that is because spatial modes allow access to a larger state space beyond the qubit, unlike polarisation. However, unlike...
Ms
charmaine sibanda
(stellenbosch university)
27/06/2018, 16:40
Track C - Photonics
Oral Presentation
With worldwide production of polymers pegged at over 300 million tonnes (2017), there’s need for sustainable options for production, waste management and recycling of polymers [1]. This high demand of polymers has made them become one of the most important materials in various industrial and biomedical sectors. These materials have shown interesting and unique physical properties that change...
Dr
Kumar Promod
(Department of Physics, University of the Free state South Africa)
29/06/2018, 10:00
Track C - Photonics
Oral Presentation
Copper soda-lime glass nanocomposites were synthesized by an ion exchange method followed by thermal annealing in atmosphere. Ultraviolet-visible absorption spectroscopy and transmission electron microscopy confirmed the presence of Cu nanoclusters embedded in the glass matrix. The size of the Cu nanoclusters has been found to increase with increasing the annealing temperature and time. The...
Mr
Simon Nnalue Ogugua
(University of the Free State)
29/06/2018, 10:20
Track C - Photonics
Oral Presentation
Effects of annealing on luminescent properties of mixed lanthanum oxyorthosilicates co-doped Dy3+ and Pr3+ phosphors.
Simon N. Ogugua1, Hendrik C. Swart1, Odireleng M. Ntwaeaborwa2
1 Department of Physics, University of the Free State, Bloemfontein, ZA9300, South Africa.
2School of Physics, University of the Witwatersrand, Private Bag 3, Wits, 2050, South Africa.
For the past three...
Mr
Andre de Bruyn
(Laser Research Institute, Stellenbosch University)
29/06/2018, 10:40
Track C - Photonics
Oral Presentation
Resonant Ionisation Spectroscopy (RIS) refers to the selective excitation of a particular atomic isotope to an excited state by means of resonant light, followed by photo-ionisation and ion detection. 68Zn and 67Zn are important stable nuclides in medicine and industry as used to produce Gallium isotopes (68Ga and 67Ga) that are used in medical imaging such as Positron Emission Tomography...
Mr
Arthur Harrison
(University of Pretoria)
29/06/2018, 11:20
Track C - Photonics
Oral Presentation
The remarkable efficiency and regulation of the initial, photophysical events in photosynthesis are a great source of inspiration for solar technologies. To make a physical solar cell using bio-inspired processes requires a simple, practicable model that makes use of the same photophysical principles as natural light-harvesting systems but with reduced molecular size and complexity. The...
Ms
Channay Naidoo
(Laser Research Centre, University of Johannesburg)
29/06/2018, 11:40
Track C - Photonics
Oral Presentation
Metastatic melanoma is the 6th most common cancer diagnosed worldwide, with approximately 100, 000 annual related deaths. Photodynamic therapy (PDT) is a photochemotherapeutic cancer treatment that utilizes a photosensitizer (PS) drug that, when activated by laser light at a specific wavelength, yields reactive oxygen species (ROS), which in turn induces cell death. However, due to the passive...
Mr
Farooq Kyeyune
(University of Pretoria)
29/06/2018, 12:00
Track C - Photonics
Oral Presentation
Light-harvesting complex II (LHCII) is the main antenna complex in photosystem II (PSII) of plants and serves as a model for biological multichromophoric systems with great potential in biophotovoltaic applications. However, in these applications, the use of LHCII is limited by the relatively small portion (less than 1%) of solar energy that can be absorbed by a single protein monolayer. The...
Ms
Dimakatso Mokoena
(Laser Research Center, University of Johannesburg)
29/06/2018, 12:20
Track C - Photonics
Oral Presentation
Diabetes is associated with complicated wound healing and rapid wound progression which may be due to cells that fail to proliferate and differentiate, thus leading to ulcers and limb amputations. The administration of photobiomodulation (PBM) has been associated with increased cellular proliferation, a decrease in wound repair duration and an increase in wound flexibility. Most studies...
Mr
Sajan George
(University of Johannesburg)
29/06/2018, 12:40
Track C - Photonics
Oral Presentation
Laser-induced differentiation of Adipose Stem Cells to neuron-like cells
Sajan George and Heidi Abrahamse*
Laser Research Centre, Faculty of Health Sciences, University of Johannesburg, Doornfontein, South Africa
The effect of lasers (light) on living cells and organs, referred as photobiomodulation (PBM) is capable of bringing morphological and functional changes to stem cells....
