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Engineering the photonic density of states (PDOS) using resonant microcavities or periodic dielectric media gives control over a plethora of classical and quantum phenomena associated with light. Here, we show that nanostructured metamaterials with hyperbolic dispersion, possess a broad bandwidth singularity in the PDOS, an effect not present in any other photonic system, which allows remarkable control over light-matter interactions. A spectacular manifestation of this non-resonant PDOS alteration is the broadband Purcell effect, an enhancement in the spontaneous emission of a light source, which ultimately leads to a device that can efficiently harness a single photon from an isolated emitter. Our approach differs from conventional resonant Purcell effect routes to single photon sources with a limitation in bandwidth, which places restrictions on the probable use of such methods for practical device applications, especially at room temperature. The proposed metadevice, useful for applications from quantum communications to biosensing also opens up the possibility of using metamaterials to probe the quantum electrodynamic properties of atoms and artificial atoms such as quantum dots

Optical microscopy is an invaluable tool for studies of materials and biological entities. With the current progress in nanotechnology and microbiology imaging tools with ever increasing spatial resolution are required. However, the spatial resolution of the conventional microscopy is limited by the diffraction of light waves to a value of the order of 200 nm. Thus, viruses, proteins, DNA molecules and many other samples are impossible to visualize using a regular microscope. The new ways to overcome this limitation may be based on the concept of superlens introduced by J. Pendry [1]. This concept relies on the use of materials which have negative refractive index in the visible frequency range. Even though superlens imaging has been demonstrated in recent experiments [2], this technique is still limited by the fact that magnification of the planar superlens is equal to 1.In this communication we introduce a new design of the magnifying superlens and demonstrate it in the experiment. Our design has some common features with the recently proposed "optical hyperlens" [3], "metamaterial crystal lens" [4], and the plasmon-assisted microscopy technique [5]. The internal structure of the magnifying superlens is shown in Fig

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PACS numbers: 78.20.Ci, 42.25.Bs, 71.36.+c, The unprecedented degree of control of the local dielectric permittivity ε ik and magnetic permeability μ ik tensors in electromagnetic metamaterials has fueled recent explosion in novel device ideas, and resulted in discovery of new physical phenomena. Advances in experimental design and theoretical understanding of metamaterials greatly benefited from the field theoretical ideas developed to describe physics in curvilinear space-time. Theoretical investigation of the 2T higher dimensional space-time models had been pioneered by Paul Dirac [12]. More recent examples can be found in [13,14]. Metric signature change events (in which a phase transition occurs between say (-,+,+,+) and (-,-,+,+) space-time signature) are being studied in Bose-Einstein condensates and in some modified gravitation theories (see ref. [15], and the references therein). In general, it is predicted that a quantum field theory residing on a spacetime undergoing a signature change reacts violently to the imposition of the signature change. Both the total number and the total energy of the particles generated in a signature change event are formally infinite [15]. Therefore, such a metric signature transition can be called a "Big Flash", which shares some similarities with the cosmological "Big Bang". A metamaterial model of a metric signature change event should be extremely interesting to observe. Unlike usual phase transitions, in which the physical system changes while the background metric is intact, the signature change transition affects the underlying background metric experienced by the system. Therefore, signature change events