In electrodynamics <http://en.wikipedia.org/wiki/Electrodynamics>, *circular polarization*[1]<http://en.wikipedia.org/wiki/Circular_polarization#cite_note-1>of an electromagnetic wave <http://en.wikipedia.org/wiki/Electromagnetic_wave> is a polarization<http://en.wikipedia.org/wiki/Polarization_(waves)>in which the electric field of the passing wave does not change strength but only changes direction in a rotary manner. Circular polarization
http://en.wikipedia.org/wiki/Circular_polarization In electrodynamics the strength and direction of an electric field<http://en.wikipedia.org/wiki/Electric_field>is defined by what is called an electric field vector <http://en.wikipedia.org/wiki/Electric_field_vector>. In the case of a circularly polarized wave, as seen in the accompanying animation, the tip of the electric field vector<http://en.wikipedia.org/wiki/Euclidean_vector>, at a given point in space, describes a circle as time progresses. If the wave is frozen in time, the electric field vector of the wave describes a helix along the direction of propagation. Circular polarization is a limiting case<http://en.wikipedia.org/wiki/Limiting_case>of the more general condition of elliptical polarization <http://en.wikipedia.org/wiki/Elliptical_polarization>. The other special case <http://en.wikipedia.org/wiki/Special_case> is the easier-to-understand linear polarization<http://en.wikipedia.org/wiki/Linear_polarization> . The phenomenon of polarization arises as a consequence of the fact that light <http://en.wikipedia.org/wiki/Electromagnetic_radiation> behaves as a two-dimensional transverse wave<http://en.wikipedia.org/wiki/Transverse_wave#Explanation> . The magnetic field vector is pointed in the direction of propagation of the light wave and emanates from a really small center of the circular light wave. --------------------------------------------- distortion of circular polarization of light waves result in anapole magnetic monopoles, where the magnetic field derives from the light wave comeing from a POINT. *http://arxiv.org/ftp/arxiv/**papers/1204/1204.3564.pdf*<http://arxiv.org/ftp/arxiv/papers/1204/1204.3564.pdf> *Half-solitons in a polariton quantum fluid behave like magnetic monopoles* One kind of spin-phase topological defects already reported in polariton quantum fluids are the so-called half-vortices23,24. Different from integer quantized vortices in scalar fluids where the phase winds from zero to 2p when going around the vortex core25, half vortices present a simultaneous rotation of p of both the phase and the polarisation angle around their core. These objects have been recently predicted to behave like monopoles26, but experiments have so far reported half-vortices pinned to local inhomogeneities of the sample24, preventing any probing of the monopole physics. In this work we report the generation of a different kind of vectorial topological excitation in a flowing polariton condensate, oblique dark half-solitons. They are characterised by a notch in the polariton density of the fluid, and a simultaneous phase and polarisation rotation of p 2 in the condensate wavefunction across the soliton27 (as opposed to a phase jump of p for dark solitons in scalar condensates28). This is manifested in the *circular polarisation basis* as a deep notch present in only one polarisation component. We map the polarisation and phase of these objects evidencing their complex spin structure, and we show that they are indeed accelerated by the action of the intrinsic effective magnetic field present in our microcavities, thus behaving as magnetic monopoles . * Any field that is concentrated into point source has extreme strength.*
