Volume 11 Issue 1, January 2017

The field of photovoltaics has grown tremendously over the past decade and in 2015 solar cell deployments accounted for 20% of the expansion of global electricity capacity.

Optical communication systems have traditionally sent the most information possible through a few spatial channels to minimize cost and maximize density. Energy constraints now compel systems at the longest and shortest distances to employ a new strategy of using more spatial channels, each carrying less data.

Worldwide research efforts on plasmonics and metamaterials have been growing exponentially for the past ten years. Will this course hold true over the next decade?

The development of free-electron lasers with improved brilliance, diffraction-limited synchrotrons and compact table-top sources all point to a healthy future for X-ray science.

A new set of imaging techniques that take advantage of scattered light may soon lead to key advances in biomedical optics, providing access to depths well beyond what is currently possible with ballistic light.

In the future, sources of intense terahertz radiation will open up an era of extreme terahertz science featuring nonlinear light–matter interactions and applications in spectroscopy and imaging.

Quantum optics is a well-established field that spans from fundamental physics to quantum information science. In the coming decade, areas including computation, communication and metrology are all likely to experience scientific and technological advances supported by this far-reaching research field.

From displays to solar cells, the field of organic optoelectronics has come a long way over the past 50 years, but the realization of an electrically pumped organic laser remains elusive. The answer may lie with hybrid organic–inorganic materials called perovskites.

This Review covers optical clock networks that are established to synchronize remote optical clocks. Further upgrading of optical clock networks and their impact on a future redefinition of time are also discussed.

Experimental data supported by simulations indicate that the trajectories of relativistic electron bunches can be controlled at the attosecond timescale by precise adjustment of the relative phase in a two-colour field scheme. An enhancement in the harmonic yield is also reported.

Rabi oscillations with a decay time of 26.7 μs are observed in a system comprising the electron spins in a diamond nitrogen–vacancy centre and a superconducting microwave cavity. Such oscillations are achieved by engineering the spectral hole burning of the spin ensemble.

A time-averaged intensity distribution of terahertz waves is imaged by converting terahertz waves to optical fluorescence. The conversion becomes possible by exciting Cs atoms to a Rydberg state. The image acquisition time is 40 ms.

Ultralow-noise microwave signals are generated at 12 GHz by a low-noise fibre-based frequency comb and cutting-edge photodetection techniques. The microwave signals have a fractional frequency stability below 6.5 × 10^–16 at 1 s and a timing noise floor below 41 zs Hz^–1/2.

Optical clocks with a record low zero-dead-time instability of 6 × 10^–17 at 1 second are demonstrated in two cold-ytterbium systems. The two systems are interrogated by a shared optical local oscillator to nearly eliminate the Dick effect.

By employing electro-optic phase modulation, a time-lens imaging system is demonstrated for single-photon pulses. Such a system achieves wavelength-preserving sixfold bandwidth compression of single-photon states in the near-infrared spectral region.

A regular stream of single photons is generated from a terrylene molecule. The metallodielectric planar antenna, applied to a terrylene molecule, and the optical excitation scheme are developed to achieve intensity fluctuations 40% below the sub-shot-noise limit.

New design of Pt(II) phosphors yield near-infrared organic light-emitting diodes with high efficiency and brightness.