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.
Collective behavior is an unusual phenomenon in condensed-matter physics. When quantum spins interact together as a system, they produce unique effects not seen in individual particles. Understanding how quantum spins interact ...
Condensed Matter
Jan 20, 2026
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744
Whether in a smartphone or laptop, semiconductors form the basis of modern electronics and accompany us constantly in everyday life. The processes taking place inside these materials are the subject of ongoing research. When ...
Condensed Matter
Jan 19, 2026
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1244
The Politecnico di Milano has created the first integrated and fully tunable device based on spin waves, opening up new possibilities for the telecommunications of the future, far beyond current 5G and 6G standards. The study, ...
Condensed Matter
Jan 13, 2026
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117
A collaboration between Stuart Parkin's group at the Max Planck Institute of Microstructure Physics in Halle (Saale) and Claudia Felser's group at the Max Planck Institute for Chemical Physics of Solids in Dresden has realized ...
Condensed Matter
Jan 12, 2026
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92
Controlling light at dimensions thousands of times smaller than the thickness of a human hair is one of the pillars of modern nanotechnology.
Nanophysics
Dec 29, 2025
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108
NIMS, in joint research with the University of Tokyo, AIST, the University of Osaka, and Tohoku University, have proposed a novel method for actively controlling heat flow in solids by utilizing the transport of magnons—quasiparticles ...
Condensed Matter
Dec 29, 2025
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25
Excitons are pairs of bound negatively charged electrons and positively charged holes that form in semiconductors, enabling the transport of energy in electronic devices. These pairs of charge carriers also emerge in transition ...
Faster, more efficient, and more versatile—these are the expectations for the technology that will produce our energy and handle information in the future. But how can these expectations be met? A major breakthrough in physics ...
Condensed Matter
Dec 18, 2025
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75
Researchers from CIC nanoGUNE, in collaboration with the Donostia International Physics Center (DIPC) and the Center for Materials Physics (CFM), have experimentally observed and theoretically verified flat-band ultrastrong ...
Nanophysics
Dec 18, 2025
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29
Researchers from the University of Innsbruck, the Collège de France, and the Université Libre de Bruxelles have developed a simple yet powerful method to reveal anyons—exotic quantum particles that are neither bosons nor ...
Condensed Matter
Dec 18, 2025
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