{
  "id": 11920813,
  "title": "Giant fluctuations of focused light reveal hidden correlations in opaque materials",
  "url": "https://urgent.news/2026/10/04/giant-fluctuations-of-focused-light-reveal-hidden-correlations-in",
  "topic": "science",
  "section": "Science",
  "published": "2026-10-04T12:00:01.000Z",
  "source": {
    "name": "Phys.org",
    "slug": "phys-org",
    "url": "https://phys.org/news/2026-09-giant-fluctuations-focused-reveal-hidden.html"
  },
  "original_language": "en",
  "account": "When light passes through a dense, disordered medium like biological tissue, it takes many different paths, resulting in a speckle pattern. Researchers from Saint Louis University and the French National Center for Scientific Research have discovered that fluctuations in the brightness of focused light through such materials can reveal hidden correlations within the medium. By combining optical experiments, simulations, and random-matrix theory, the scientists found that these fluctuations carry a \"fingerprint\" of the light's journey through the material. This \"enhancement factor\" is not just a measure of focusing performance, but also an observable that can provide insights into the complex scattering properties of the medium. The researchers used finite-size Laguerre–Wishart random-matrix statistics to create a statistical reference for the enhancement factor, which accurately predicts both its average value and fluctuations in the absence of long-range correlations. However, experiments revealed that these fluctuations can be up to several times larger than the theoretical prediction, especially in thicker materials. These \"giant fluctuations\" are not just random noise, but evidence of long-range mesoscopic correlations in the scattering medium. These correlations are fundamental to understanding wave transport in disordered systems and are related to phenomena like universal conductance fluctuations and Anderson localization. The study shows that these giant fluctuations provide a more sensitive way to detect these long-range correlations than previous methods, which required measuring large transmission matrices. This could have practical implications for applications like high-contrast imaging, optical metrology, and other areas where strong, reproducible focusing through complex media is important.",
  "summary": "When light travels through a strongly scattering material, such as biological tissue or other disordered opaque media, it follows many different paths and produces a seemingly random speckle pattern. Wavefront shaping makes it possible to control this complex interference and focus light through such materials.",
  "key_points": [
    "Fluctuations in focused light brightness reveal hidden correlations in opaque materials",
    "These correlations are fundamental to understanding wave transport in disordered systems"
  ],
  "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."
}