Optica Congratulates Francis Halzen, Winner of the 2026 Nobel Prize in Physics

06 October 2026

Optica Congratulates Francis Halzen, Winner of the 2026 Nobel Prize in Physics

Optica, Advancing Optics and Photonics Worldwide, warmly congratulates Francis Halzen (University of Wisconsin - Madison, USA) who was today awarded the 2026 Nobel Prize in Physics "for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin."

Neutrinos-tiny, electrically neutral elementary particles-interact very weakly with matter, making them exceptionally difficult to detect. That same property allows them to travel enormous cosmic distances virtually undisturbed and escape dense environments that may be opaque to light. Therefore, they provide scientists with a unique window into the sources and mechanisms that drive some of the most extreme cosmic phenomena, including high-energy particle accelerators.

The IceCube Neutrino Observatory, a cubic kilometer volume of Antarctic ice instrumented with 5,160 light sensors, demonstrated that these elusive particles can be detected in sufficient numbers and traced to astrophysical sources, helping establish high-energy neutrino astronomy as a new field.

Optical science played an enabling role in the development of the underlying detection approach. In a 1997 Applied Optics paper (https://doi.org/10.1364/AO.36.004168), Halzen and his colleagues in the AMANDA Collaboration characterized the wavelength-dependent absorption of light in deep Antarctic ice using laser pulses transmitted between embedded emitters and receivers. These experiments helped establish an understanding of the optical properties of South Pole ice, which are critical to detecting the faint Cherenkov light generated by charged particles produced in neutrino interactions.

About Halzen

Francis Halzen received his PhD in 1969 from KU Leuven, Belgium. He is the Gregory Breit Professor and Vilas Research Professor at the University of Wisconsin - Madison, USA, and principal investigator of the IceCube Neutrino Observatory. Halzen has played a leading role in the development of IceCube and its predecessor, AMANDA, helping establish the use of deep Antarctic ice as a medium for detecting high-energy neutrinos and enabling the discovery of neutrinos of astrophysical origin.

Reference

The AMANDA Collaboration; Askebjer, Per; Barwick, Steven W.; Bergström, Lars; Bouchta, Adam; Carius, Staffan; Dalberg, Eva; Engel, Kevin; Erlandsson, Bengt; Goobar, Ariel; Gray, Lori; Hallgren, Allan; Halzen, Francis; Heukenkamp, Hans; Hulth, Per Olof; Hundertmark, Stephan; Jacobsen, John; Karle, Albrecht; Kandhadai, Vijaya; Liubarsky, Igor; Lowder, Doug; Miller, Tim; Mock, Pat; Morse, Robert M.; Porrata, Rodin; Price, P. Buford; Richards, Austin; Rubinstein, Hector; Schneider, Eric; Spiering, Christian; Streicher, Ole; Sun, Qin; Thon, Thorsten; Tilav, Serap; Wischnewski, Ralf; Walck, Christian; Yodh, Gaurang B. "Optical properties of deep ice at the South Pole: absorption." Applied Optics, 36(18), 4168-4180. (1997) https://doi.org/10.1364/AO.36.004168

About Optica

Optica, Advancing Optics and Photonics Worldwide, is the Society dedicated to promoting the generation, application, archiving and dissemination of knowledge in the field. Founded in 1916, it is the leading organization for scientists, engineers, business professionals, students and others interested in the science of light. Optica's renowned publications, meetings, online resources and in-person activities fuel discoveries, shape real-life applications and accelerate scientific, technical and educational achievement. Discover more at: Optica.org

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