Cloaks work with a mirror

Cloaks are such inspiring objects that intrigue both physical and atheistic innovative can only be quested by physicists to the end. Now a work from Singapore reported a cloak working with a mirrow: the thing of a 2mm to be hided is placed on a mirror and covered by a cloak made of calcite. One only perceives the mirror but not thing under carpet [PRL 106, 033901 (2011)].

Invisibility cloaks, a subject that usually occurs in science fiction and myths, have attracted wide interest recently because of their possible realization. The biggest challenge to true invisibility is known to be the cloaking of a macroscopic object in the broad range of wavelengths visible to the human eye. Here we experimentally solve this problem by incorporating the principle of transformation optics into a
conventional optical lens fabrication with low-cost materials and simple manufacturing techniques. A transparent cloak made of two pieces of calcite is created. This cloak is able to conceal a macroscopic object with a maximum height of 2 mm, larger than 3500 free-space-wavelength, inside a transparent liquid environment. Its working bandwidth encompassing red, green, and blue light is also demonstrated.