Magnetic trapping of light

Light is one of the most important and versatile phenomenon in nature. Like a courier, it can transfer information from one point to another. Like an alchemist, it can alter matter. More specifically, it can initiate and moderate many processes in chemistry, biology and condensed matter. In our understanding of nature, light always plays a vital role. Interaction of photons with matter provides fascinating avenues for basic as well as applied research. Electromagnetism is the fundamental mediator of all interactions in atomic and condensed matter physics. It is rare to see an entirely new electromagnetic phenomenon. However, Mehta and co-workers' have reported one such phenomenon. They observed that upon application of external magnetic field on a dispersion of micron-sized magnetic spheres stably dispersed in ferrofluid, through which monochromatic, coherent light was passing gets trapped inside the suspension for a critical value of applied field.