Articles in 2017

Nanomagnets are often used to build artificial systems that are geometrically frustrated, but when quasiperiodic ordering is introduced, an unusual ground state can form, with an ordered skeletal structure surrounding groups of degenerate macrospins.

Theory and experiment show that quantum correlations violate the instrumental test—a common statistical method used to estimate the strength of causal relationships between two variables.

Large spin–orbit coupling can be induced when graphene interfaces with semiconducting transition metal dichalcogenides, leading to strongly anisotropic spin dynamics. As a result, orientation-dependent spin relaxation is observed.

Droplets moving on the surface of a vibrating fluid bath mimic the behaviour of electrons in quantum corrals. Introducing submerged features in the bath can even drive the droplets to excite modes that induce effects reminiscent of quantum mirages.

A significant enhancement in the effective mass of Dirac-like quasiparticles residing near a nodal loop in the electronic band structure provides evidence for strong correlation effects in a topological semimetal.

A liquid droplet is shown to slide across a solid surface subject to friction forces analogous with those between two solids. The phenomenon is generic, and closes a gap in our understanding of liquid–solid friction.

A tracing of the phase-ordering kinetics of a charge density wave system demonstrates the potential of ultrafast low-energy electron diffraction for studying phase transitions and ordering phenomena at surfaces and in low-dimensional systems.

Topological defects in a turbulent active nematic on a toroidal surface are shown to segregate in regions of opposite curvature. Simulations suggest that this behaviour may be controlled — or even suppressed — by tuning the level of activity.

Experimental study of the Kondo insulator SmB₆ provides an alternative route to realize a Fermi surface in the absence of a conventional Fermi liquid.

The simplest lattice model that allows the investigation of superconductivity with attractive interactions is realized using ultracold quantum gas. The experimental observation provides a lower bound on the strength of s-wave pairing correlations.

Resonant electron attachment and subsequent dissociation of diatomic molecules is shown to exhibit spatial asymmetry as a consequence of coherent excitation and subsequent interference between reaction pathways.

A theoretical framework for interpreting recent observations of light-induced superconductivity in alkali-doped fullerides is proposed and developed.

Fundamental fingerprints of topological orders may be characterized uniquely and purely by experimental means. Here the authors provide a proof of principle demonstration using interferometric measurement in a two-dimensional lattice system.

Electron filling criterion can guide the search for new topological materials with nodal-point or nodal-line Fermi surfaces.

In a hot, under-dense plasma, eight input beams are combined into a single, well-collimated beam, whose energy is more than triple than that of any incident beam. This shows how nonlinear interactions in plasmas can produce optics beams at much higher intensity than possible in solids.

Measurements of the electron wavepackets produced by photoionizing noble gas atoms with an XUV harmonic comb enable the reconstruction of the effective binding potential: a new technique that could be extended to molecules.

The energy needed to control a network is related to the links between driver and non-driver nodes, a linear control theory suggests. Applying the theory to connectome data reveals that diverse dynamics in brain networks incur small energetic cost.

Ultrashort high-intensity laser pulses change the properties of dielectrics in different ways. One unexpected outcome is light amplification in an excited dielectric, observed in a two-colour pump–probe experiment.

A thermodynamic study of doped single crystals of NbFe₂ reveals the phase diagram of this system as a function of temperature, magnetic field and Nb doping — which includes an unusual quantum tricritical point.

A candidate for efficient broadband quantum memory at telecommunication wavelengths is identified. The long coherence time and the efficient optical spin pumping demonstrated in the experiment make it practical for spin-wave storage.