Volume 6 Issue 4, April 2012

Low-cost manufacturing, high yields and seamless on-chip integration with electronics are often touted as the guaranteed benefits of silicon photonics, but is this really the case? Michael Hochberg and colleagues explain that the situation is much more complex in reality.

Fractals, shapes comprised of self-similar parts, are not merely prescribed linear structures. A wide class of fractals can also arise from the rich dynamics inherent to nonlinear optics.

Worldwide sales in the laser market grew to US$7.5 billion in 2011, recovering from a slump brought on by economic turmoil.

Fibre lasers capable of producing stable, axially symmetric ring-like radiation from an extended surface may prove to be an important new light source for applications in medical imaging, sensing, bio-sensing and security systems.

Providing sufficient gain to overcome loss remains a fundamental challenge for light amplification in miniaturized plasmonic devices. Ongoing research gives hope for a cautious but optimistic outlook.

Linking distant quantum memories with light has been a goal of the quantum information community for many years. A team at the University of Geneva has now demonstrated that memories made from rare-earth-ion-doped crystals can be connected using a single photon.

Techniques for the targeted optical stimulation of neurons may offer new ways to tackle medical problems such as heart defects, epilepsy, Parkinson's, blindness and hearing loss.

Researchers demonstrate the creation of an eight-photon Schrödinger-cat state with genuine multipartite entanglement by developing noise-reduction multiphoton interferometer and post-selection detection. The ability to control eight individual photons will enable new multiphoton entanglement experiments in previously inaccessible parameter regimes.

Researchers realize a zero-angular-momentum radial-emission laser by filling a cylindrical photonic crystal fibre cavity with a microfluidic gain medium. Control of the electromagnetic fields is provided by electrically contacted and independently addressable liquid-crystal microchannels in the fibre.

Researchers observe heralded entanglement between two neodymium ensembles doped in Nd³⁺:Y₂SiO₅ crystals separated by 1.3 cm. The high level of interference indicates that the stored entanglement does not significantly decohere over a period of 33 ns. They demonstrate that rare-earth-ion ensembles have the potential to form compact, stable and coherent quantum network nodes.

Researchers demonstrate that an individual Mollow sideband channel of the resonance fluorescence from an InGaAs quantum dot can act as an efficient single-photon source. The central frequency of the bright and narrow sideband emission can be changed by laser detuning over a range spanning 15 times the emission linewidth.

By exciting few-cycle femtosecond laser pulses at 397 nm in near-resonance with the direct bandgap of silicon, researchers experimentally demonstrate coherent phonon generation in silicon at a fundamental frequency of 15.6 THz and all-optical >100 THz frequency comb generation.

Using photonic crystal cavities with a buried heterostructure design, scientists demonstrate all-optical RAM at power levels 300 times lower than previous attempts. The 30 nW devices could enable low-power large-scale optical RAM systems for handling high-bit-rate optical signals.

High-efficiency fluorescent organic light-emitting diodes have been realized by employing custom-designed molecules that make it possible to convert non-radiative triplet states into radiative singlet states.

Researchers consider electromagnetic dissipation in metamaterials and plasmonic systems comprised of various materials. They predict that graphene and high-temperature superconductors may not be suitable for practical resonant metamaterial applications and are unlikely to outperform conventional metals in plasmonics. Transition metals, alkali metals and transparent conducting oxides are also discussed.

New research suggests that graphene is not a 'miracle material' for metamaterials and plasmonics. Nature Photonics spoke to Philippe Tassin about what makes a good conductor for these applications.