{
  "id": 190175,
  "title": "Electric field reverses phonon chirality and spin direction in ferroelectric crystal",
  "url": "https://urgent.news/2026/08/05/electric-field-reverses-phonon-chirality-and-spin-direction-in",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-05T19:00:06.000Z",
  "source": {
    "name": "Phys.org",
    "slug": "phys-org",
    "url": "https://phys.org/news/2026-08-electric-field-reverses-phonon-chirality.html"
  },
  "original_language": "en",
  "account": "Researchers have discovered that applying an electric field to a ferroelectric crystal causes the chirality of phonons within it to reverse. Phonons, which are groups of atoms that move in circular patterns when excited by energy, propagate the angular momentum that governs spin. The direction of this spin is dictated by chirality, a property that makes a molecule or material unable to be superimposed on its mirror image. This finding could lead to the development of faster and more energy-efficient spintronic devices, which utilize the spin of electrons for information processing. Xiaotong Li, the lead researcher from North Carolina State University, explains that the team used a ferroelectric molecular crystal called triglycine sulfate (TGS) because its structural chirality and ferroelectric polarization are linked. When TGS is in its ferroelectric phase, the application of an electric field causes the dipole moments to align in one direction. This polarization and chirality can then be switched under the electric field, enabling active control of phonon chirality and spin. The researchers measured the spins on the surface of the crystal and their polarization direction to confirm that the spin polarization direction reversed when chirality was switched. The study, published in Nature Communications, was supported by simulations that revealed the atomic motions behind the observed effects.",
  "summary": "Chiral phonons are groups of atoms that move in a circular direction when excited by an energy source, such as heat. As the phonons move through a material, they propagate that circular motion, or angular momentum, through the material. The angular momentum serves as the source of spin, and the chirality dictates the direction of the spin, enabling spin control in spintronics.",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}