Articles in 2010

Graphene has a random edge structure. According to theory, this dirty and random edge affects the topological nature of bilayer graphene, which accounts for measurement discrepancies across different experimental probes.

For an ideal topological insulator, the metallic surface states should be easy to measure using transport techniques; however, the bulk is not completely insulating. Improving the ‘leaky’ bulk state proves crucial for measuring the surface Dirac fermions, including correlation effects.

Networks of atom–cavity systems necessarily require that single atoms sit near dielectric interfaces. Real-time monitoring of caesium atoms just 100 nm from the surface of a micro-toroid resonator now demonstrates that the Casimir effect plays an important role in these systems.

Recent advances in the formulation of the second law of thermodynamics have rekindled interest in the connections between statistical mechanics and information processing. Now a 'Brownian computer' has approached the theoretical limits set by the rejuvenated second law. Or has it?

Carbon nanotubes are not superconductors but they can carry a supercurrent injected from a superconducting contact. Analysis of the tunnelling spectra of a nanotube connecting two superconductors reveals details of the bound electron–hole states that carry such a supercurrent.

Although carbon nanotubes are not superconductors they can carry supercurrents injected from superconducting contacts. Analysis of the tunnelling spectra of a nanotube connecting two superconductors reveals the detailed electronic structure of discrete entangled electron–hole states that carry the resulting supercurrent.

Feedback mechanisms such as the ‘demon’ in Maxwell’s well-known thought experiment can, in principle, enable the transformation of information into energy, without violating the second law of thermodynamics. Such information-to-energy conversion by feedback control has now been demonstrated experimentally.

Quantum information is often thought of in terms of manipulating discrete qubits. But continuous variables can also carry data. A method for storing continuous-variable states of light for up to a millisecond in room-temperature memories is now demonstrated.

A three-dimensional periodic structure focuses acoustic waves to a spot size that is one fiftieth of the wavelength—beating the classical diffraction limit by a long way. The device could lead to improved resolution for ultrasound imaging.

A dark exciton is an electron–hole pair with a very long radiative recombination time. Whereas their ’bright’ counterparts are studied in depth, dark states in quantum dots are often regarded as a nuisance. Now, a technique has been found for optically accessing dark excitons, which might make them more useful than first thought.

The rotation of polarized light in certain materials when subject to a magnetic field is known as the Faraday effect. Remarkably, just one atomic layer of graphene exhibits Faraday rotations that would only be measurable in other materials many hundreds of micrometres thick.

Fifty years ago, Abdus Salam envisaged a 'world centre' for theorists. Now the institute that he founded is adapting to a changing world and to changing ways of doing science.

A school on computational materials science that drew expert teachers and talented participants marks a new approach to the development of research in Africa.

The quantum kagome lattice is a fundamental but experimentally elusive frustrated magnet. Neutron spectroscopy now reveals the ground state and elementary excitations of a deformed kagome lattice in which the quantum spins form an exotic pinwheel valence-bond state.

Achievement of the United Nations' Millenium Development Goals is by no means guaranteed, but there is heartening progress in the promotion of science for development.