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A supersolid with continuous translational symmetry breaking along one direction is realized by symmetrically coupling a Bose–Einstein condensate to the modes of two optical cavities.

By periodically modulating the position of degenerate fermions unidirectionally in a three-dimensional optical lattice, antiferromagnetic correlations in this many-body system can be reduced, enhanced or even switched to ferromagnetic correlations.

The dynamic structure factor is measured in condensed matter systems via neutron scattering, but this is not applicable to ultracold atomic gases. Here, the authors show how it can be measured relying on the strongly enhanced inelastic scattering of photons off a quantum gas in an optical cavity.

Quantized conductance in the transport of neutral atoms is observed in an optically produced channel — either a quantum point contact or a quantum wire — between two atom reservoirs; the lowest non-zero conductance value is the universal conductance quantum, the reciprocal of Planck’s constant.

Connecting two superfluid reservoirs leads to both particle and entropy flow between the systems. Now, a direct measurement of the entropy current and production in ultracold quantum gases reveals how superfluidity enhances entropy transport.

A tunable optical lattice is used to engineer massless and massive Dirac fermions and realize the topological transition at which two Dirac points merge and annihilate each other.

Thouless pumping is the quantization of charge transport through the adiabatic variation of a system’s parameters. The robustness and breakdown of pumping under variations in interparticle interactions have now been shown with ultracold atoms in an optical lattice.

A mechanism for self-oscillating pumping in a quantum gas is demonstrated using a Bose–Einstein condensate coupled to a dissipative cavity, where a particle current is observed without external periodic driving.

Ultracold atoms can model single-order quantum phases, but coupling of different order parameters has not been shown. Here, this is demonstrated using two optical resonators, facilitating exploration of multiple-order systems such as multiferroics.

Direct measurements of the conduction properties of strongly interacting ultracold fermions reveal the well-known drop of resistance associated with the onset of superfluidity.

There has been considerable recent experimental progress in cavity quantum electrodynamics, involving the quantum-mechanical coupling of cold atoms to a confined light field. Here, the trapped atoms are in the form of a Bose—Einstein condensate, and so all couple identically to a single mode of the light field.

An interferometric implementation of Young’s double-slit experiment is used to probe quantum correlations that are manifest in the distribution of local spin fluctuations in a two-component degenerate Fermi gas.

This paper reports the formation of a Mott insulator of a repulsively interacting two-component Fermi gas in an optical lattice. It is identified by three features: a drastic suppression of doubly occupied lattice sites, a strong reduction of the compressibility inferred from the response of double occupancy to an increase in atom number, and the appearance of a gapped mode in the excitation spectrum. The results pave the way for further studies of the Mott insulator, including spin-ordering and ultimately the question of d-wave superfluidity.

A phase transition occurs when a physical system suddenly changes state, for instance when it melts or freezes. The Dicke model describes a collective matter–light interaction and has been predicted to show a quantum phase transition. Here, this quantum phase transition has been realized in an open system formed by a Bose–Einstein condensate coupled to an optical cavity. Surprisingly, the atoms are observed to self-organize into a supersolid phase.

Non-trivial Peierls phases that depend on the site occupations for ultracold fermions in an optical lattice have been engineered in a Floquet approach, providing a fundamental ingredient for a density-dependent gauge field acting on ultracold matter.

The observation of Bose–Einstein condensation in an atomic gas was a seminal result. Two-dimensional gases are more complex, and an intriguing interference experiment has exposed a different superfluid transition.

The Haldane model, which predicts complex topological states of matter, has been implemented by placing ultracold atoms in a tunable optical lattice that was deformed and shaken.

The simplest form of the Hubbard model includes only on-site interactions, but by placing an optical lattice filled with ultracold rubidium atoms into an optical cavity the Hubbard model is implemented with competing long- and short-range interactions; four phases emerge, namely, a superfluid phase, a Mott insulating phase, a supersolid phase and a charge density wave phase.

Achieving ordered quantum phases on demand is crucial for future quantum technologies. Here, the authors propose an experiment with a quantum gas in an optical cavity, demonstrating multiple phases with both spatial and temporal order, all tunable on demand.

The Kondo effect is a prototypical strongly correlated phenomenon, in which a strong, localized repulsion gives rise to a many body resonance that controls the low-energy physics of a metal. Here, the authors show that the same effect can be induced by purely dissipative means through localized two body losses, which provides a nontrivial–and experimentally relevant– application of nonlinear dissipation.