Research: Hearing the Light: Stray-Field Noise from the Emergent Photon in Quantum Spin Ice

In this work the authors propose a practical way to detect elusive "emergent photons"—particles that behave analogously to light but exist only inside magnetic materials known as quantum spin liquids. Quantum spin liquids are exotic magnetic states in which the magnetic moments remain fluctuating and disordered even as the temperature approaches absolute zero, rather than freezing into a regular pattern as in an ordinary magnet. For decades, identifying unambiguous experimental signatures of these phases in real materials has been a central challenge in condensed matter physics. 

This work explores a novel route to detect quantum spin liquid signatures. When the emergent photons encounter a material boundary they leak magnetic noise into the surrounding environment. This escaping noise carries clear fingerprints of the underlying quantum state and should be detectable using existing nanoscale magnetic sensors. The results therefore provide a promising experimental pathway toward confirming the existence of a long-sought quantum state of matter.

G. K. Naik, J. N. Hallén, N. C. Jayarama, R. Moessner, C. R. Laumann,
Hearing the Light: Stray-Field Noise from the Emergent Photon in Quantum Spin Ice,
Phys. Rev. Lett. 136, 256705 (2026) (arXiv)