Research articles

Many studies on the properties of the recently discovered ferropnictide superconductors report seemingly contradictory results. A theoretical study suggests that these contradictions might be resolved by considering such materials as having a strongly magnetic ground state whose domain boundaries fluctuate, preventing their experimental detection.

Techniques for reconstructing an object’s microstructure from its diffraction pattern have substantially improved the future imaging potential of next-generation X-ray sources. Yet the same techniques can already be applied to conventional electron microscopes, to extend their resolution to below an ångström.

ARPES measurements of the ‘failed’ superconductor LBCO-1/8 suggest that its pseudogap phase consists of two distinct components. The result could be an important clue into the nature of this phase in the copper oxide superconductors.

The exploration of the Jaynes–Cummings Hamiltonian in a circuit-QED system—where an ‘artificial atom’ made of a superconducting circuit is strongly coupled to a microwave field—provides direct evidence for nonlinearities due to quantum mechanics on the level of single atoms and photons.

An experiment demonstrating the generation of subfemtosecond pulses of light through the interaction of laser light with a solid target underlines the potential of this approach to lead to a new generation of intense sources of attosecond pulses.

A general approach to simplifying quantum logic circuits—the ‘programs’ of quantum computers—is described and demonstrated on a platform based on photonic qubits.

Two independent experiments that demonstrate memories for single quantum excitations with storage times on the order of a millisecond—two orders of magnitude longer than reported so far—should help to bring practical long-distance quantum-communication networks a step closer.

Two independent experiments that demonstrate memories for single quantum excitations with storage times of the order of a millisecond—two orders of magnitude longer than reported so far—should help to bring practical long-distance quantum-communication networks a step closer.

An array of superconducting nanocircuits has been designed that provides built-in protection from environmental noises. Such ‘topologically protected’ qubits could lead the way to a scalable architecture for practical quantum computation.

High-resolution electron microscope images collected in real time demonstrates the occurrence of multiple intermediary phases during the crystallization of a metal phosphate. The observations represent the first atomic-scale demonstration of Wilhelm Ostwald’s ‘rule of stages’ proposed over a century ago.

An accurate determination of the size and diffusion length of excitons generated with single-walled nanotubes supports the Wannier–Mott picture of their behaviour, and improves the outlook for the use of nanotubes in optoelectronics and biosensing applications.

Low-temperature thermal-transport measurements of a frustrated organic magnet in which a quantum spin-liquid is believed to exist, suggest that the emergence of this state is accompanied by a spin-gap. This contradicts previous studies conducted at higher temperatures, suggesting that our understanding of this system should be re-evaluated.

The ability to wiggle and stretch individual superconducting vortices with nanoscale precision enables unprecedented insight into their dynamics and the properties of the superconductor that supports them.

In quantum mechanics, measurement has a fundamentally different role than in classical physics. Now a general method has been devised to characterize a quantum measurement device, completing the suite of so-called tomography techniques required to fully specify an experiment.

Analysis of the ejection of electrons in a plane perpendicular to an incident electron beam reveals unexpected differences between the ionization behaviour of atoms and molecules. For molecules that have nuclei at their centres of mass, the angular distribution of emitted electrons is similar to that of atoms. But for those that don’t, the shape of this distribution is qualitatively different.

In many real-world processes that can be mapped onto complex networks—from cell signalling to transporting people—communication between distant nodes is surprisingly efficient, considering that no node has a full view of the entire network. A framework sets out to explain why ‘navigability’ is so efficient in these networks.

An algorithm that reconstructs the structure of an object in flight from the diffraction pattern generated by exposing it to an ultrashort burst of X-rays should enhance the potential of free-electron lasers for studying individual molecules, virus and nanoparticles.

High-resolution angle-resolved photoemission measurements of the Fermi-surface and superconducting gap of high-quality C₆Ca crystals should help resolve the nature of the high-temperature superconducting behaviour of this and related intercalated graphite materials.

Transport measurements in a high-temperature superconductor provide evidence that the so-called pseudogap phase ends at a quantum critical point located inside the superconducting dome in the phase diagram of cuprates.

Two independent experiments demonstrate that quantum entanglement that has been lost in decoherence processes can be recovered. For the first time such ’entanglement distillation’ has been achieved for states of light that are entangled in continuous variables, which should help to increase the distance over which quantum information can be distributed.