The Canonical Form of the Rabi Hamiltonian

The Rabi Hamiltonian, describing the coupling of a two-level system to a single quantized boson mode, is studied in the Bargmann-Fock representation. The corresponding system of differential equations is transformed into a canonical form in which all regular singularities between zero and infinity have been removed. The canonical or Birkhoff-transformed equations give rise to a two-dimensional eigenvalue problem, involving the energy and a transformational parameter which affects the coupling strength. The known isolated exact solutions of the Rabi Hamiltonian are found to correspond to the uncoupled form of the canonical system.Comment: 17 pages, LaTeX, no figures, to appear in J.Math.Phy

Production of syndiotactic polystyrene powder for part manufacturing through SLS

Selective laser sintering (SLS) is a well-established additive manufacturing (AM) process. While AM originally found its use as rapid prototyping technique, it is nowadays more and more considered for the production of actual end-use parts. A widely acknowledged hindrance in the evolution of this technology is the limited range of materials available for processing with SLS, making the application window rather small. Introducing new materials with the correct morphology and thermal requirements for SLS could broaden this window and give rise to new products. This research aims at identifying such promising materials, considering the relevant requirements for selecting and processing a new material. Considered foremost within this manuscript is the processability of syndiotactic polystyrene from pellet form into spherical particles of 50-90 μm without significantly changing their properties. Regarding processing methods, the focus of this work is on solution based techniques (single phase precipitation, emulsion precipitation) instead of more conventional mechanical processing methods (ball milling) as these are believed to be more accessible and more suitable as a precursor step for a wide range of processing technique