Reviews & Analysis

The controlled 'catch and release' of individual quantum-information-carrying photons is an important ingredient for achieving scalable quantum networking. Recently, researchers at the Max Planck Institute of Quantum Optics succeeded in this task in two separate systems.

Photonic quasicrystals are specially designed aperiodic materials that possess long-range order and are capable of transmitting light. Contrary to intuition, introducing disorder can be used to enhance the propagation of light through such labyrinth structures.

The use of terahertz pulses to 'gate' interlayer charge transport in a superconductor could lead to a variety of new and interesting applications.

Wavelength-tunable ultraviolet light sources are required for a wide range of applications, but are typically difficult to manufacture and operate. A simple gas-filled optical fibre that performs efficient frequency conversion from the infrared to the deep-ultraviolet could be a promising answer.

A four-year collaboration between Japan and Europe aims to increase the efficiency of concentrator solar cells to beyond 45%.

Green fluorescent protein — an important biological imaging tool for many years — now forms the foundation of the first cellular laser.

Lensless X-ray imaging is no longer limited to monochromatic sources. A new approach that is compatible with polychromatic beams can increase the efficiency of diffractive imaging experiments, thus significantly reducing exposure times.

Semiconductor light-emitting diodes may soon replace mercury lamps as the ultraviolet source of choice in a wide range of applications. Researchers around the world are now racing to increase the efficiency and output power of such ultraviolet solid-state devices.

Researchers in Japan have now extended the capability of light-in-flight holography to femtosecond pulse durations in the visible wavelength range.

The demonstration of a phase-sensitive optical amplifier with a noise figure of just 1.1 dB — three times lower than that of a conventional amplifier — could help significantly extend the reach of optical communications systems.

The use of carbon nanotube electrodes and new device geometries is enhancing the performance of organic light-emitting transistors.

A scattering medium such as biological tissue distorts the propagation of light pulses in both space and time, making tasks such as focusing and imaging problematic. Fortunately, careful manipulation of the light field's spatial phase prior to entering the medium can help mitigate such distortions and open new prospects for nonlinear microscopy.

Structures exhibiting variable refractive index could soon represent a simpler and more flexible alternative to metamaterials for making sophisticated high-performance lenses.

Increasing bandwidth capacities while reducing the number of power-hungry components required to achieve this goal may seem like a contradiction in terms. However, researchers in Europe have now demonstrated a feasible technique whereby a single laser can carry optical data at transmission rates of more than 20 Tbit s⁻¹.