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.
Physicists at The City College of New York have demonstrated a new way to transfer microwave signals onto light using magnetic waves inside a layered semiconductor. The work establishes a materials platform for building interfaces ...
Optics & Photonics
Sep 17, 2026
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A Stanford team has documented the first direct observation of quantum jumps of sound in a mechanical resonator, completing an arc of scientific exploration that started more than 100 years ago.
Quantum Physics
Sep 17, 2026
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525
Researchers at the University of Eastern Finland have uncovered two complementary mechanisms that govern coherence in miniaturized lasers composed of metallic nanoparticle arrays incorporated into an optical gain material, ...
Optics & Photonics
Sep 16, 2026
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16
Xufeng Zhang is using magnets to make computers more power efficient at the quantum level. The Northeastern professor of electrical and computer engineering recently published two papers highlighting small-scale magnetic ...
Quantum Physics
Sep 15, 2026
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33
In 1931, physicist Hans Bethe predicted that, in certain one-dimensional quantum systems, particles can bind together to form multi-particle states known as Bethe strings. Unlike ordinary molecules, which are held together ...
Quantum Physics
Sep 14, 2026
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Metallic nanostructures are exceptionally effective at concentrating light into tiny volumes, while dielectric nanostructures excel at storing light with minimal energy loss. Combining these complementary properties has traditionally ...
Nanophysics
Sep 11, 2026
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36
Superconductors are materials that carry electricity with zero resistance below specific temperatures. Many of these materials become superconducting at very low temperatures, yet some enter superconducting phases at higher ...
For decades, physicists have searched for dark matter, the invisible substance thought to make up roughly 85% of all matter in the universe. Although its gravitational influence shapes galaxies and the large-scale structure ...
General Physics
Sep 9, 2026
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41
Atoms in a material are rarely still. They jiggle back and forth in collective lattice vibrations known as phonons. Their motion can also carry a rotational element: In 2023, scientists at PSI experimentally proved the existence ...
Condensed Matter
Sep 7, 2026
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22
Heat, it turns out, has a memory. A cooling cup of coffee may not seem particularly thoughtful. At the scale of a kitchen, heat appears to follow a straightforward rule: it moves from warmer places to cooler ones. Leave the ...
General Physics
Sep 3, 2026
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