Volume 15 Issue 6, June 2019

The detection of the quantum state of tens of neutral atoms arranged in arrays has reached a new record fidelity. This brings fault-tolerant quantum computation and simulation closer to reality.

A two-state hopping experiment combined with a dynamical systems model reveals that cancer cells are deterministically driven across barriers, whereas normal cells cross only with the help of stochastic fluctuations.

While Bose–Einstein condensates of atoms were achieved in the mid-1990s, extending the regime of quantum degeneracy to polar molecules took another two decades of dedicated work. The researchers that contributed to this achievement span many generations of students in many different laboratories around the world.

An electrical interferometer device has detected interference patterns that suggest anyons could be conclusively demonstrated in the near future.

Triggered by the fluctuations of the electromagnetic vacuum, parametric down-conversion offers a new primary radiation standard based on quantum nonlinear optics.

The measured change in the fundamental frequency of a superconducting resonator coupled to a tunnel junction reveals a broadband constant Lamb shift, which is typically inaccessible in atomic systems.

A technique based on the coherent splitting of the atoms’ wavefunctions according to their internal states in an optical lattice allows the measurement of neutral-atom qubits in a three-dimensional array with extremely high fidelity, up to 99.94%.

Drag effects between interacting particles in nearby layers can impact their motion. Here, this idea is extended to angular momentum in domain walls in a synthetic antiferromagnet and synchronization is observed.

Collagen networks go from soft to rigid when strained, but in tissue they exist in a soft matrix. An enhanced stiffness and delayed strain-stiffening is now revealed in the composite, which may explain the remarkable sensitivity of living tissue.

Bacteria and other helical microswimmers are known to swim faster in non-Newtonian fluids. Coarse-grained simulations suggest the increase may be due to a polymer depletion effect near the body and flagellum, inducing a slip velocity at the surface.

Getting a picture of a d or f atomic orbital has been a challenge, but the X-ray scattering technique reported here enables direct transition from core s orbitals to the d orbitals so that their spatial shape can be mapped with no need for modelling.

An interferometer device demonstrates the interference of fractional quantum Hall effect edge states. This is a big step towards braiding non-Abelian anyons.

A scattering resonance associated with quasi-bound diatomic levels trapped behind the centrifugal barrier has been observed in a quantum-degenerate potassium gas. Various measurements reveal the d-wave character of the collisions.

The second-order topological states—chiral hinge states—are predicted in axion insulators, ferromagnetic insulating materials with quantized electromagnetic response. The authors predict such states to occur in Sm-doped Bi₂Se₃.

By tuning the geometry of a two-dimensional sonic crystal, its one-dimensional helical edge states become gapped and zero-dimensional topological corner states emerge. The band topology is thus manifested in a hierarchy of dimensions.

In situ measurements based on coherent X-ray spectroscopy are performed during the epitaxial growth of gallium nitride films, revealing a memory effect in the arrangement of islands formed on successive crystal layers.

Two-state micropatterns offer a unique platform to study cell migration. An equation of motion is inferred from a large ensemble of trajectories, revealing key differences in the nonlinear dynamics of healthy and cancerous cells.

The same type of polymer network deforms cell membranes inward, to absorb external material, and outward, to facilitate signal transmission. Experiments and theory show that these deformations are regulated by membrane tension and network mesh size.

Bacteria swimming near surfaces can get trapped in circular trajectories that lead nowhere, hindering efficient surface exploration. A harmful strain of bacteria is now shown to circumvent the problem by exploiting transient surface adhesion events.

The way that we understand free space has varied wildly since our first conception of the vacuum. And how we measure the void has proven just as changeable, as Karl Jousten explains.