Volume 9 Issue 11, November 2015

The concept of optical computing is reintroduced with an important new twist — optical computing not as a digital machine, but as an analog engine able to serve as a hardware accelerator for existing electronic computers.

Techniques for determining Stokes parameters, which fully define the polarization state of a wave, require multiple measurements, thus potentially leading to inaccuracies. Researchers now show how to simultaneously determine the parameters for visible light using periodic metal structures.

Crossing two focused laser beams with opposite circular polarization makes the production and application of circularly polarized light in the extreme ultraviolet and soft X-ray spectral regions considerably easier and more efficient.

Integrated nano-optical memories may help overcome the limitations of communication speeds and energy costs in electronic chips. Now, using nanoscale phase-change materials researchers have realized the first multi-bit all-optical non-volatile memories with a very small footprint.

Next-generation wireless communication, high-harmonic generation of sub-cycle pulses and ultrafast probing of the excitation dynamics of materials were all topics of discussion at this year's IRMMW-THz conference in Hong Kong.

Using a leaky-wave antenna, free-space-to-waveguide frequency-division multiplexing and demultiplexing are demonstrated in the terahertz range. Both the frequency and the spectral bandwidth of multiplexed channels can be independently controlled.

A compact source that generates sub-two-cycle-duration pulses with an average power of 0.1 W spanning 6.8–16.4 μm combines the properties of power scalability, high repetition rate and phase coherence for the first time in this spectral region.

Researchers use phase-change materials to demonstrate an integrated optical memory with 13.4 pJ switching energy.

A laser is made from the two-dimensional material WS₂ by embedding it into a microdisk resonator.

Most metamaterial experiments occur in bulk transmission geometries. Here researchers demonstrate integrated in-plane zero-index metamaterials.

Scientists have demonstrated non-collinear circularly polarized high-harmonic generation and showed that this method generates bright circularly polarized extreme-ultraviolet beams with both left and right helicity simultaneously.

A set of principal modes that maintain pulse properties and spatial coherence despite propagation in 100 metres of multimode fibre are observed.

A diffractive dielectric grid placed between the anode and substrate of an organic light-emitting device is found to significantly enhance the extraction of light.

A protocol to recover states of optical continuous-variable entanglement is developed based on approximate heralded noiseless amplification. The degraded entanglement is completely recovered no matter how significant these losses are.