Articles in 2020

An interferometer device is used to detect the quantum-mechanical phase that is gained when two anyons are braided around each other. The fractional value of the phase proves that these quasiparticles are neither bosons nor fermions.

The non-zero geometric phase acquired by the braiding of vortex modes in photonic waveguide lattices demonstrates their potential to serve as a platform for the study of both Abelian and non-Abelian braiding in bosonic systems.

Ultracold alkaline-earth fermionic atoms with large number of nuclear spin states possess SU(N) symmetry. That deeply affects their interaction properties, and allows a Fermi gas of these atoms to be cooled quickly to the quantum degenerate regime.

The authors investigate out-of-equilibrium crystallization of a binary mixture of sphere-like nanoparticles in small droplets. They observe the spontaneous formation of an icosahedral structure with stable MgCu₂ phases, which are promising for photonic applications.

The unpredictability of evolution makes it difficult to deal with drug resistance because over the course of a treatment there may be mutations that we cannot predict. The authors propose to use quantum methods to control the speed and distribution of potential evolutionary outcomes.

The authors engineer Escherichia coli into two distinct strains with tunable motility. The induced control of motility leads to the formation of patterns through a self-organizing mechanism that is specific to multi-component active systems.

High-quality WSe₂–MoSe₂ heterostructures support strong coupling between the two layers, which is associated with tight hybridization and effective charge separation. In these structures, the bands of the interlayer excitons can be pressure-engineered.

The presence of axion-like dark matter candidates is expected to induce an oscillating magnetic field, enhanced by a ferromagnet. Limits on the electromagnetic coupling strength of axion-like particles are reported over a mass range spanning three decades.

For a scenario of two separated but entangled observers, inequalities are derived from three fundamental assumptions. An experiment shows that these inequalities can be violated if quantum evolution is controllable on the scale of an observer.

The flow of fluid, such as mucus in the human respiratory tract, can affect biological function. Here the authors show that the hydrodynamic interactions mediated by mucus are essential for the directional coordination of ciliary beating in the lungs.

Analogous to the radiation-pressure coupling known in optomechanics, photon-pressure interaction between superconducting circuits can reach the strong coupling regime, which allows flexible control of the electromagnetic resonator’s quantum state.

The authors investigate the relationship between the volume of malignant tumours and their metabolic processes using a large dataset of patients with cancer. They find that cancers follow a superlinear metabolic scaling law, which implies that the proliferation of cancer cells accelerates with increasing volume.

Higher-dimensional entanglement between two photons can be preserved for a photon passing through a complex medium by applying an appropriate scrambling operation on the entangled partner that does not enter the complex medium.

An optomechanical cavity comprising a re-entrant cavity and membrane resonators can be tuned in and out of the Casimir regime. At the transition between the two regimes, the mechanical resonators exhibit a change in stiffness—the Casimir spring.

A magnetic impurity is placed on the tip of a scanning tunnelling microscope, allowing direct tunnelling between two Yu–Shiba–Rusinov bound states. This technique can probe and enhance the impurity state lifetime.

Scanning tunnelling microscopy is enhanced by microwave radiation that allows photon-assisted tunnelling processes. This technique is demonstrated on impurity states in a superconductor.

An adaptive heterodyne technique with a Josephson parametric amplifier detector allows a high-precision single-shot canonical phase measurement on a one-photon wave packet, complementing near-ideal measurements of photon number or field amplitude.

A transient intermediate complex in a chemical reaction—formed from collisions between molecules with a few atoms—is observed under ultracold conditions. Its lifetime can be directly measured after suppression of the photo-excitation process.

Weyl points in three-dimensional systems with certain symmetry carry non-Abelian topological charges, which can be transformed via non-trivial phase factors that arise upon braiding these points inside the reciprocal space.

The ability to create optomechanically squeezed light at room temperature across a frequency range in the audio band could improve the measurement precision of future interferometric detectors for gravitational waves.