polariteli

Polariteli is a term used in some languages to refer to polaritons, a class of quasiparticles that arise when photons interact strongly with excitations in a material. In practice, polariteli describes the hybrid light-mmatter states that result from this strong coupling, in which the light and matter components mix to form a single, propagating excitation.

The most studied examples are exciton-polaritons, formed when photons confined in a microcavity couple with excitons—electron–hole pairs—in a semiconductor quantum well. Other families include phonon-polaritons, where photons couple to optical phonons in crystals, and plasmon-polaritons, which involve coupling to collective electron oscillations on metal surfaces or graphene. Polariteli inherit properties from both constituents: the photonic part gives very light effective mass and fast propagation, while the material part provides interactions and nonlinearity.

Polariteli form under a regime of strong coupling, where the interaction rate between light and matter exceeds losses. This leads to characteristic anticrossings and normal-mode splitting in their dispersion relations, observable in optical spectra. In two-dimensional semiconductor microcavities, exciton-polaritons can undergo Bose–Einstein-like condensation and form coherent, macroscopic states, enabling low-threshold polariton lasers and studies of quantum fluids of light.

Applications of polariteli span ultrafast photonics, low-power coherent light sources, and quantum simulation of many-body physics. Ongoing research aims to improve their lifetimes, achieve room-temperature operation, and integrate polaritonic devices with existing semiconductor technologies. See also polariton, exciton, phonon-polariton, plasmon-polariton.