Reviews & Analysis

Laser-based Doppler cooling is a popular method for reducing the temperature of atoms, but it is limited to dilute gases. Now, researchers in Germany have demonstrated a laser scheme for cooling a highly dense gas mixture.

Mechanically manipulating the lateral size of the lasing mode of a single-mode terahertz quantum cascade laser provides a new and robust method for widely and continuously tuning its emission wavelength.

The integration of an optically pumped switch in a quantum cascade laser device yields a semiconductor terahertz amplifier that promises to extend the capabilities of time-domain spectroscopy.

The demonstration that polarized laser pulses can control molecular velocities through the dipole force suggests that the cooling of molecules using light may soon be within reach.

Quantum memory is important for a range of application including quantum information processing, matching various processes within a quantum devices, as a tool to convert photons to photons-on-demand and for implementation of long-distance quantum communication using quantum repeaters. Here, state-of-the-art optical quantum memory is reviewed.

We have just witnessed the birth of the first quantum technology based on encoding information in light for quantum key distribution. The quantum nature of light seems destined to continue to have a central role in future technologies. Here we provide a broad review of photonics for quantum technologies touching on topics including secure communication with photons, quantum information processing, quantum lithography and integrated quantum photonics.

This review highlights the recent progress which has been made towards improved single-photon detector technologies and the impact these developments will have on quantum optics and quantum information science.

Stanford University researchers have demonstrated the potential of single SiC whiskers to function as narrowband infrared emitters that have controllable emission characteristics.

Customizing the refractive index of wells and barriers in a periodic array of quantum wells yields a way to control the reflectivity and dispersion of an excitonic lattice. The result is a new method for slowing or modulating light.

Controlling the transport of charge carriers between two semiconductor nanostructures using an acoustic wave yields a high-repetition-rate source of single photons with tunable emission energy.

Researchers at Stanford University and the Max Planck Institute for Polymer Research have demonstrated fluorescence enhancements ten times greater than previously demonstrated, by placing single fluorophores in an optical bowtie nano-antenna.

Visual encryption, manipulation of terahertz waves and the improved surface-treatment of GaN crystals were all topics of discussion at this year's JSAP meeting in Toyama, Japan.

The news that spherical droplets of a liquid crystal can function as whispering-gallery-mode microresonators with an unprecedented width of wavelength tunability could be good news for fabricating new kinds of sensors and lasers.

The use of cascaded nonlinear silicon waveguides that function as 'time lenses' is providing new opportunities for generating and measuring ultrafast optical waveforms.

Interconnects and switches relying on excitons — quasiparticles consisting of bound electron–hole pairs — may offer a promising energy-efficient alternative to electrons in wires for future electronic circuitry.