Quasiparticles & collective excitations as a research area investigates emergent, effective degrees of freedom in many-body systems, where interactions among underlying microscopic constituents give rise to particle-like or mode-like entities such as phonons, magnons, polarons, excitons, and plasmons. This field focuses on formulating and analyzing low-energy effective theories, dispersion relations, lifetimes, and interaction vertices of these excitations using frameworks such as many-body perturbation theory, Green’s functions, field-theoretic methods, and numerical many-body techniques. It plays a central role in understanding transport, superconductivity, topological phases, and nonequilibrium dynamics in condensed matter, ultracold atomic systems, and related quantum materials.
When the number of electrons matches host lattice sites in a material, strong interactions between electrons can cause them to arrange themselves into an orderly pattern, forming what is known as an electron crystal. This ...
Quantum Physics
Jul 30, 2024
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Charge density waves are quantum phenomena occurring in some materials, which involve a static modulation of conduction electrons and the periodic distortion of the lattice. These waves have been observed in numerous condensed ...
In a paper published in the Applied Physics Letters journal, a group of scientists demonstrated that under optical excitation, a polariton condensate can simultaneously occupy two closely spaced energy levels, which results ...
Condensed Matter
Jul 9, 2024
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89
A group of physicists specialized in solid-state physics from the University of Cologne and international collaborators have examined crystals made from the material BaCO2V2O8 in the Cologne laboratory.
Quantum Physics
Jun 27, 2024
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118
Exciton-polariton lasers, renowned for their low-power operation, have long tantalized researchers with their promise for practical low-energy applications. However, until now, a clean measurement of the laser's linewidth, ...
Optics & Photonics
Jun 18, 2024
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190
Researchers in the field of nanophotonics have spent significant time in recent years investigating fascinating concepts known as polaritons and/or plexcitons. These ideas revolve around the strong coupling of light photons ...
Nanophysics
Jun 14, 2024
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129
Halide perovskites are a class of materials with an underlying structure resembling that of mineral perovskites, but with X sites occupied by halide ions, while their A and B sites are occupied by cations. These materials ...
Magnetic monopoles are elementary particles with isolated magnetic charges in three dimensions. In other words, they behave as isolated north or south poles of a magnet. Magnetic monopoles have attracted continuous research ...
Condensed Matter
Jun 12, 2024
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115
A team of Monash researchers have uncovered for the first time the full effects of interactions between exciton-polaritons and their associated dark excitonic reservoir. The study, "Polaronic polariton quasiparticles in a ...
Condensed Matter
Jun 12, 2024
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90
Thousands of particles of light can merge into a type of "super photon" under suitable conditions. Physicists call such a state a photon Bose-Einstein condensate.
Optics & Photonics
Jun 7, 2024
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