The growth and collapse of a vapour bubble inside a microtube is studied both experimentally and theoretically. The length of the bubble, and the velocity and acceleration of its interface, are obtained from a high-speed image recording (typically 1.25 × 105 fps) for various energy inputs and two tube diameters. To understand the underlying dynamics of the system, two theoretical models are compared with experiment. A model based on a discontinuous time dependence of the vapour pressure inside the bubble is at variance with the data. It proves necessary to account in greater detail for the time dependence of the vapour pressure. A new model is proposed for this purpose which includes heat transfer in addition to inertia and viscous friction. Both the data and the model show that the vapour pressure decreases with time continuously instead of abruptly. The length, velocity and acceleration from the numerical simulations are found to be in good agreement with experimental data. Both the experiments and simulations clearly indicate that thermal effects play an important role throughout the whole growth and collapse process.

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In this paper we investigate the properties of self induced transparency (SIT) solitons, propagating in a Λ-type medium. We find that the interaction between SIT solitons can lead to trapping with their phase preserved in the ground state coherence of the medium. These phases can be altered in a systematic way by the application of appropriate light fields, such as additional SIT solitons. Furthermore, multiple independent SIT solitons can be made to propagate as bi-solitons through their mutual interaction with a separate light field. Finally, we demonstrate that control of the SIT soliton phase can be used to implement an optical exclusive-or gate.

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