In a significant scientific advancement, Italian researchers have successfully converted light into a "supersolid," a novel quantum state of matter. This achievement, detailed in the journal Nature in March 2025, marks a major step forward in quantum physics and offers potential for new photonic and quantum technologies.
Unlike traditional methods of creating supersolids, which involve cooling atoms to near absolute zero, this pioneering study manipulated light directly. The team employed a specialized semiconductor material, aluminum and gallium arsenide, structured with intricate narrow grooves. By directing a laser onto this patterned surface, they generated quasi-particles called polaritons, which are formed from the interaction of photons and excitons within the semiconductor.
Confined within a microscopic architecture, these polaritons organized into a crystalline structure while maintaining superfluid properties. The creation of this state required highly precise measurements, including the detection of minute density modulations in the polaritonic state, as small as a few thousandths. This accuracy was crucial for observing "translational symmetry breaking," a key indicator of the transition to an ordered, crystalline solid state.
This breakthrough has far-reaching implications for future technologies, with potential applications in more efficient lighting systems, advanced lubricants, and the development of neuromorphic computers. It could also accelerate progress in fields such as superconductivity and quantum computing. The research received funding from the European Union's Q-ONE and PolArt projects, highlighting the collaborative international effort behind this scientific milestone.