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arXiv · 1406.0583

Bloch Sphere Catastrophes

Samuel A. Eastwood·David M. Paganin·Timothy C. Petersen·Michael J. Morgan
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Abstract

Caustics are optical phenomena which occur when a family of rays creates an envelope of divergent intensity. Here we show that caustic surfaces also appear when a real or complex field is mapped to its order parameter manifold. We study these structures in the context of spin-1/2 fields, where the order parameter manifold is the Bloch sphere. These generic structures are a manifestation of catastrophe theory and are stable with respect to perturbations. The corresponding field configurations are also stable and represent a new type of topological defect. Equations governing the conditions for their existence and unfolding are derived.

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Samuel A. Eastwood, David M. Paganin, Timothy C. Petersen, Michael J. Morgan. 2014-06-03. Bloch Sphere Catastrophes. https://arxiv.org/abs/1406.0583

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