Recent Submissions

  • Quantum kinetic perturbation theory for near-integrable spin chains with weak long-range interactions 

    Duval, Clement; Kastner, Michael (IOP Publishing, 2019)
    For a transverse-field Ising chain with weak long-range interactions we develop a perturbative scheme, based on quantum kinetic equations, around the integrable nearest-neighbour model. We introduce, discuss, and benchmark ...
  • X-Ray microcomputed tomography in additive manufacturing : a review of the current technology and applications 

    Du Plessis, Anton; Yadroitsev, Igor; Yadroitsava, Ina; Le Roux, Stephan G. (Mary Ann Liebert, Inc., 2018)
    X-ray microcomputed tomography (microCT) has become an established method of testing and analyzing additively manufactured parts in recent years, being especially useful and accurate for dimensional measurement and porosity ...
  • Single molecule diffusion in polymeric systems 

    Sibanda, Charmaine (Stellenbosch : Stellenbosch University, 2019-04)
    ENGLISH ABSTRACT : The dynamics of thin polymeric systems were studied in this research work using the diffusion of single fluorescent molecules observed by single molecule fluorescence microscopy. A wide field single ...
  • Spectroscopy of atomic zinc inside a heat pipe: Towards resonance ionisation 

    Hattingh, Brandon Dane (Stellenbosch : Stellenbosch University, 2019-04)
    ENGLISH ABSTRACT : Zinc (Zn) reserves in South Africa are not being used to full potential. Separating Zn into its different stable isotopes drastically increases its value, as well as usefulness in certain areas such ...
  • Membrane coupled to the cytoskeleton: Fluctuations and stability 

    Gumede, Sthembiso Reuben (Stellenbosch : Stellenbosch University, 2019-04)
    ENGLISH ABSTRACT : In erythrocytes the plasma membrane is coupled to the underlying two dimensional hexagonal network of spectrin filaments through protein node complexes. There are also other protein complexes that link ...
  • Thermalisation of a two-species condensate coupled to a bosonic bath 

    Louw, Jan Cillié (Stellenbosch : Stellenbosch University, 2019-04)
    ENGLISH ABSTRACT : Motivated by recent experiments, we study the time evolution of a two-species Bose-Einstein condensate which is coupled to a bosonic bath. For the particular condensate, unconventional thermodynamics ...
  • Resonance ionization spectroscopy with time of flight mass spectrometry 

    Waso, Frederick John (Stellenbosch : Stellenbosch University, 2019-04)
    ENGLISH ABSTRACT : Resonance ionization using laser light is one of the most useful techniques for isolating radioactive isotopes and producing radioactive ion beams at accelerator facilities around the world. The aim of ...
  • Universal equilibrium scaling functions at short times after a quench 

    Karl, Markus; Cakir, Halil; Halimeh, Jad C.; Oberthaler, Markus K.; Kastner, Michael; Gasenzer, Thomas (American Physical Society, 2017)
    By analyzing spin-spin correlation functions at relatively short distances,we showthat equilibrium near-critical properties can be extracted at short times after quenches into the vicinity of a quantum critical point. The ...
  • Scattering in a three-dimensional fuzzy space 

    Kriel, J. N.; Groenewald, H. W.; Scholtz, F. G. (American Physical Society, 2017)
    We develop scattering theory in a noncommutative space defined by an su(2) coordinate algebra. By introducing a positive operator valued measure as a replacement for strong position measurements, we are able to derive ...
  • Quantum effects in the cooperative scattering of light by atomic clouds 

    Pucci, Lorenzo; Roy, Analabha; Santo, Tiago Santiago do Espirito; Kaiser, Robin; Kastner, Michael; Bachelard, Romain (American Physical Society, 2017)
    Scattering of classical light by atomic clouds induces photon-mediated effective long-range interactions between the atoms and leads to cooperative effects even at low atomic densities. We introduce a simulation technique ...
  • Phases of dipolar bosons in a bilayer geometry 

    Cinti, Fabio; Wang, Daw-Wei; Boninsegni, Massimo (American Physical Society, 2017)
    We study, by first-principles computer simulations, the low-temperature phase diagram of bosonic dipolar gases in a bilayer geometry as a function of the two control parameters, i.e., the in-plane density and the ...
  • Noninvasive measurement of dynamic correlation functions 

    Uhrich, Philipp; Castrignano, Salvatore; Uys, Hermann; Kastner, Michael (American Physical Society, 2017)
    The measurement of dynamic correlation functions of quantum systems is complicated by measurement backaction. To facilitate such measurements we introduce a protocol, based on weak ancilla-system couplings, that is ...
  • Classical and quantum filaments in the ground state of trapped dipolar Bose gases 

    Cinti, Fabio; Boninsegni, Massimo (American Physical Society, 2017)
    We study, by quantum Monte Carlo simulations, the ground state of a harmonically confined dipolar Bose gas with aligned dipole moments and with the inclusion of a repulsive two-body potential of varying range. Two different ...
  • PT-symmetric waveguide system with evidence of a third-order exceptional point 

    Schnabel, Jan; Cartarius, Holger; Main, Jorg; Wunner, Gunter; Heiss, Walter Dieter (American Physical Society, 2017)
    An experimental setup of three coupled PT -symmetric waveguides showing the characteristics of a third-order exceptional point (EP3) has been investigated by Heiss and Wunner in an idealized model of three δ-function waveguides ...
  • Structure functions of the nucleon in a soliton model 

    Takyi, Ishmael (Stellenbosch : Stellenbosch University, 2019-04)
    ENGLISH ABSTRACT : We study nucleon structure functions (both polarized and unpolarized functions) within the Nambu-Jona-Lasinio (NJL) model, in which the nucleons emerge as solitons. In particular we investigate the ...
  • Towards the improvement of spin-isospin properties in nuclear energy density functionals 

    Roca-Maza, X.; Colo, G.; Liang, H. Z.; Meng, J.; Ring, P.; Sagawa, H.; Zhao, P. W. (IOP Publishing, 2016)
    We address the problem of improving existing nuclear Energy Density Functionals (EDFs) in the spin-isospin channel. For that, we propose two different ways. The first one is to carefully take into account in the fitting ...
  • Search for highly excited states in ²⁸Si 

    Montanari, D.; Courtin, S.; Jenkins, D. G.; Diget, C.; Yavuzkanat, N.; Neveling, R.; Mira, J. P.; Nemulodi, F.; Smit, F. D.; Usman, I.; Papka, P.; Swartz, J. A.; Van Zyl, J. J.; Orce, N. (IOP Publishing, 2017)
    The theoretical and experimental determination of superdeformed states in nuclei in the mass region A≤40 has been since a long time one of the major challenges of nuclear structure studies. Despite the considerable ...
  • Influence of nuclear cluster structure in proton-induced pre-equilibrium composite particle emission 

    Cowley, A. A. (IOP Publishing, 2017)
    Recent statistical multistep analyses of the pre-equilibrium reaction⁹³Nb(p, α) at incident energies of 65 and 100 MeV are reviewed. It is shown that the α-cluster structure of the target nucleus is prominently displayed ...
  • Development of Near-IR and Beam Shaping of Mid-IR Lasers 

    Maweza, Elijah Loyiso (Stellenbosch : Stellenbosch University, 2019-04)
    ENGLISH ABSTRACT : This study seeks to produce short-pulsed laser output with high peak and average powers to meet the demand for industrial ranging applications. Q-switched lasers are suitable for this due to their ability ...
  • Examining the role of protein structural dynamics in drug resistance in Mycobacterium tuberculosis 

    Shaw, Daniel J.; Hill, Rachel E.; Simpson, Niall; Husseini, Fouad S.; Robb, Kirsty; Greetham, Gregory M.; Towrie, Michael; Parker, Anthony W.; Robinson, David; Hirst, Jonathan D.; Hoskisson, Paul A.; Hunt, Neil T. (Royal Society of Chemistry, 2017)
    Antimicrobial resistance represents a growing global health problem. The emergence of novel resistance mechanisms necessitates the development of alternative approaches to investigate the molecular fundamentals of resistance, ...

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