Volume 5 Issue 2, February 2011

New forms of advanced optical fibres featuring exotic glasses, carefully designed microstructures and cores that are either hollow, fluidic, semiconductor or piezoelectric are giving light guides a new lease of life, reports Duncan Graham-Rowe.

The discrimination of chemical species with overlapping Raman bands is now possible in real time using a stimulated Raman scattering microscope with a fast, bipolar spectral correlator.

A new woodpile-type photonic crystal nanocavity with a three-dimensional bandgap that supports lasing from embedded quantum dots paves the way for three-dimensional integrated photonic circuits and highly efficient nanolasers.

A high-resolution scheme for converting two-dimensional infrared images to the visible region has exciting consequences for applications such as night-vision technology and chemical sensing.

Optical analogues of gravity let scientists interrogate astronomical phenomena that are otherwise difficult or impossible to study.

A simple molecular gas sample can be used to achieve ultrafast optical buffering in two-dimensional optical imaging, thus serving as a promising extension of the well-developed liquid-crystal display technology.

It has long been thought that the detection of individual molecules in ambient conditions via their absorption signature was out of reach. Now, three independent research groups have developed three different methods that allow such a feat.

Researchers demonstrate the first laser confined in all three spatial dimensions by a three-dimensional photonic crystal. The device, in this case driven by quantum dots, represents the long-standing goal of achieving lasing in a cavity formed entirely by a complete-photonic-bandgap medium.

Highly sensitive absorption spectroscopy is used to image the presence of single molecules through their weak optical absorption signatures. Measurements are demonstrated at mutiple wavelengths and scanned over a 2D area to create spatial maps of absorption.

Researchers demonstrate an X-ray holography method that records two independent images spaced by a femtosecond variable time delay. The concept overcomes the time limitations of two-dimensional area detectors by superimposing the separable X-ray holograms in a single detector exposure.

Spectral modulation of a broadband pump beam allows sensitive and specific molecular imaging based on stimulated Raman scattering. Measurements of cholesterol, protein, and stearic and oleic acid are reported.

Laser spectroscopy based on the nonlinear photothermal and photoacoustic spectral resonances of nanoparticles is demonstrated. This approach will be potentially useful for applications such as multispectral imaging, multicolour cytometry, and the study of laser–nanoparticle interactions at a resolution beyond the spectral limit.

Researchers propose a new type of multiphoton entangled state and demonstrate its working principles of measurement-based quantum computation in correlation space. With four- and six-qubit states, they realize a universal set of single-qubit rotations, two-qubit entangling gates and further Deutsch's algorithm.

Christian Günther explained to Nature Photonics that holography offers great promise for capturing X-ray movies on femtosecond timescales.