Browsing by Author "Rigby, Charles Ian"

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    Development and characterisation of a Nd:YAG pumped wavelength tunable VUV light source
    (Stellenbosch : Stellenbosch University, 2016-03) Rigby, Charles Ian; Steenkamp, Christine M.; Rohwer, Erich G.; Stellenbosch University. Faculty of Science. Dept. of Physics
    ENGLISH ABSTRACT : Please refer to the full text abstract.
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    Development of a laser cooling and magneto-optical trapping experiment for Rubidium 87 atoms
    (Stellenbosch : University of Stellenbosch, 2011-03) Rigby, Charles Ian; Steenkamp, Christine M.; Rohwer, Erich G.; University of Stellenbosch. Faculty of Science. Dept. of Physics.
    ENGLISH ABSTRACT: A magneto optical trap (MOT) is capable of trapping a vapor cloud consisting of atoms cooled down to the micro Kelvin range. Three orthogonal pairs of counter-propagating laser beams of the correct circular polarisation form an optical molasses which facilitates the cooling of neutral atoms. Additionally a spatially non-uniform magnetic field produced by two current carrying coils in a Maxwell gradient configuration is used to trap the cooled atoms. In this report the effects of the trap parameters, including the laser beam intensity and frequency detuning, beam diameter and magnetic field gradient, on the number of trapped atoms are discussed. Secondly the development of an experimental setup for laser cooling and trapping of 87Rb atoms in vacuum with the aid of a MOT is presented. All trap components were implemented and characterised. The vacuum system and trapping chamber in which the cooling takes place were designed and constructed. A rubidium getter to act as a source of atoms was integrated into the vacuum system. The two external cavity diode lasers used for trapping and optical re-pumping were characterised. The optical setup required for the optical molasses was designed, constructed and characterised. Saturated absorption spectroscopy was performed to investigate the hyperfine structure of 87Rb and to frequency lock the lasers. We report on the current status of the project with regards to progress, results and future work.