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.
An international team led by the Max Born Institute has developed a new type of momentum microscopy to image magnons—the quanta of collectively excited spins—directly in two-dimensional reciprocal space using soft X-rays. ...
Nanophysics
Jun 8, 2026
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Waves of light and sound interact to drive electronic and structural changes in a perovskite crystal. At the atomic scale, nothing is ever truly still. Materials that appear perfectly rigid and motionless to the naked eye ...
Condensed Matter
Jun 5, 2026
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99
Solar panels have become more efficient over the years, but even the best designs still lose a large fraction of the energy they absorb. Scientists around the world have been searching for ways to capture more energy from ...
Optics & Photonics
May 25, 2026
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106
When a singer belts out a tune while a guitar player strums along, sound waves travel through the air, driving collective oscillations of the molecules within. Meanwhile, at the quantum level, something similar is going on. ...
Optics & Photonics
May 25, 2026
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39
A sheet of twisted carbon nanotubes has revealed a hidden talent scientists suspected for decades but had never managed to measure. Researchers at Rice University have created large, highly ordered films of chiral carbon ...
Nanophysics
May 20, 2026
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68
Quantum materials, materials with properties that are influenced by the laws of quantum mechanics, have attracted considerable attention over the past few decades. Their unique properties make these materials advantageous ...
Eighty years ago, Penn researchers J. Presper Eckert and John Mauchly launched the age of electronic computing by harnessing electrons to solve complex numerical problems with ENIAC, the world's first general-purpose electronic ...
Optics & Photonics
May 15, 2026
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713
An international team of researchers, including scientists from HZDR and Fritz Haber Institute of the Max Planck Society, for the first time directly observed how angular momentum is transferred and conserved within a crystal ...
Condensed Matter
May 12, 2026
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402
In new research published in Nature Materials, a team of researchers led by Columbia University chemist Xiaoyang Zhu, in collaboration with fellow Columbians Xavier Roy, Milan Delor, Dmitri Basov, and James McIver, has observed ...
Condensed Matter
May 11, 2026
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22
Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have demonstrated, for the first time, a single quantum of vibrational energy interacting with a single atomic spin, seeding a pathway ...
Quantum Physics
May 10, 2026
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