Singularities and Vortices in Quantum Optics

Richard J. Creswick, Harry L. Morrison

Greg Gbur

Nowthat we have discussed the general structure and properties ofoptical vortices, we come to a pair of very practical questions: how do we generate pure vortex beams and how do we measure the characteristics of a vortex? As singular optics has grown as a eld, a variety of dierent methods have been introduced for both generation and detection, eachwith its own advantages and disadvantages. In this chapter, we summarize a number of these, beginning with the most common and progressing to the most esoteric.

Lara Thompson, Philip C. E. Stamp

Jörg B. Götte, Mark R. Dennis

Optical vortices are points of zero intensity in a two dimensional, classical optical field. As first discussed by Berry and Dennis [Berry, M. V. and Dennis, M. R., "Quantum cores of optical phase singularities" Journal of Optics A 6, S178-S180 (2004)] these singularities are replaced by 'quantum cores' in a deeper level of description. In a fully quantized theory of optical fields an excited atom trapped at the singularity can emit light spontaneously and hence soften the perfect zero of an optical vortex. More recently Barnett [Barnett, S. M., "On the quantum cores of a optical vortex," Journal of Modern Optics 55, 2279-2292 (2008)] presented a more realistic analysis of quantum cores which accounts for the effect of the trapping potential on the transition dynamics inside a vortex core. Here, we revisit the scenario of emission near an optical vortex in the realistic setting of Barnett.

Michael Berry, Mark R. Dennis

The nodal line singularities (optical vortices) of classical scalar optics are smoothed in quantum optics, because of spontaneous emission into unoccupied modes. The radius of the 'quantum core' surrounding each classical singularity is proportional to ??. A trapped excited atom, steered into a nodal line of the classical field, is a possible detector for the effect. Analogous phenomena are anticipated for other waves, for example sound, where the silence at a nodal line is disturbed by pressure fluctuations of the fluid molecules.

F. T. Arecchi, Robert G. Harrison