0000000000410384
AUTHOR
Roope Sarala
Simulation environment for the C14-experiment
In this thesis, a simulation environment utilizing Geant4 simulation toolkit was constructed to study the C14 experiment located at the Pyhäsalmi Mine, Finland. The C14 experiment aims to find a liquid scintillator sample with the least amount of 14C, the radioactive isotope of carbon, with concentration preferably less than 10^-18. The scintillator detector used in the experiment consists of a 1.6 liter cylindrical vessel filled with liquid scintillator, two 20 cm conical light guides connected to the ends of the vessel and two low-background photomultiplier tubes to detect scintillator light. In addition, the detector is covered with a reflecting foil. The simulation environment was used …
Cross-Kerr nonlinearity: a stability analysis
We analyse the combined effect of the radiation-pressure and cross-Kerr nonlinearity on the stationary solution of the dynamics of a nanomechanical resonator interacting with an electromagnetic cavity. Within this setup, we show how the optical bistability picture induced by the radiation-pressure force is modified by the presence of the cross-Kerr interaction term. More specifically, we show how the optically bistable region, characterising the pure radiation-pressure case, is reduced by the presence of a cross-Kerr coupling term. At the same time, the upper unstable branch is extended by the presence of a moderate cross-Kerr term, while it is reduced for larger values of the cross-Kerr co…