Demonstration of Universal Logic Gates in Optical Microresonators.

Whispering gallery mode optical microresonators allow the realisation of nonlinear optical phenomena at previously unattainably low powers. Accordingly, they are an exciting area of research - providing both opportunities for research into fundamental physics, and technological platforms.
The concept of optical computing seeks to replace the electronic components seen in modern computers with optical ones. It is predicted that the higher bandwidth available in optics will lead to significant improvements in processing speeds for certain problems, particularly in machine learning and data science. Requiring the combination of multiple input signals, computation is an intrinsically nonlinear problem and optical computing has been hindered by the diffculty of serving nonlinearities in optics. For this reason, optical microresonators are a promising contender for fabricating optical logic gates. This report details the realisation of a logic gate in an optical microresonator. First, the theory is discussed, culminating in the designs of gates that utilise the Kerr nonlinearity to execute logical operation. Subsequently, the experimental setup and considerations are discussed before the results are presented, demonstrating optical logic.

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