Abstract 2D and 3D solitons and related states, such as quantum droplets, can appear in
optical systems, atomic Bose–Einstein condensates (BECs) and liquid crystals, among other …

Recently a new type of system exhibiting spontaneous coherence has emerged—the
exciton–polariton condensate. Exciton–polaritons (or polaritons for short) are bosonic …

Two-dimensional atomic crystals of graphene, as well as transition-metal dichalcogenides,
have emerged as a class of materials that demonstrate strong interaction with light. This …

Exciton polaritons, the part-light and part-matter quasiparticles in semiconductor optical
cavities, are promising for exploring Bose–Einstein condensation, non-equilibrium many …

Bound states in the continuum (BICs),–are peculiar topological states that, when realized in
a planar photonic crystal lattice, are symmetry-protected from radiating in the far field despite …

Superfluidity—the suppression of scattering in a quantum fluid at velocities below a critical
value—is one of the most striking manifestations of the collective behaviour typical of Bose …

Abstract A Bose–Einstein condensate (BEC) is a state of matter in which extensive collective
coherence leads to intriguing macroscopic quantum phenomena. In crystalline …

This article reviews recent theoretical and experimental advances in the fundamental
understanding and active control of quantum fluids of light in nonlinear optical systems. In …

Quantum fluids exhibit quantum mechanical effects at the macroscopic level, which contrast
strongly with classical fluids. Gain-dissipative solid-state exciton-polaritons systems are …

Under the right conditions, cavity polaritons form a macroscopic condensate in the ground
state. The fascinating nonlinear behaviour of this condensate is largely dictated by the …