For the first time in history, scientists have successfully converted light into a supersolid—a paradoxical state of matter that combines the structural rigidity of a solid with the frictionless flow of a superfluid. This breakthrough, led by researchers at CNR Nanotec in Italy, marks a significant milestone in quantum physics, providing new opportunities for both fundamental research and technological advancements.
Understanding Supersolids
Matter typically exists in one of four well-known states: solid, liquid, gas, or plasma. However, at temperatures near absolute zero, quantum mechanics introduces new and exotic phases of matter. One such phase is the supersolid, which was first theorized in the 1960s and experimentally confirmed in 2017 using ultracold atomic gases. Supersolids exhibit an ordered, crystal-like structure while simultaneously flowing without friction, a property normally associated with superfluids.
Traditionally, the formation of supersolids required precise atomic interactions and extremely low temperatures, making their study highly challenging. However, the recent discovery that light itself can exhibit supersolid behavior presents a more accessible and scalable approach to studying this quantum phenomenon.
How Scientists Created a Supersolid from Light
The researchers achieved this breakthrough by utilizing a semiconductor platform composed of gallium arsenide. By directing laser light onto this material, they generated polaritons—hybrid quasiparticles formed from the interaction of photons (light) and excitons (electron-hole pairs). These polaritons condensed into a supersolid state, forming an ordered structure while maintaining fluid-like movement.
The experiment revealed that as photons entered the system, they initially behaved incoherently. However, as more photons were added, they began forming a Bose-Einstein condensate (BEC), a quantum state where multiple particles occupy the lowest energy level. Through a process called parametric scattering, satellite condensates formed in a structured arrangement, confirming that the photons had adopted a supersolid state.
Confirming the Supersolid State
To verify that the newly formed matter was indeed a supersolid, scientists examined two key properties: its periodic spatial structure and its frictionless flow. Observations confirmed that the photons organized into a repeating lattice-like pattern, characteristic of a solid, while maintaining the ability to flow without resistance, like a superfluid. This provided conclusive evidence that a supersolid state had been achieved using light.
Implications for Science and Technology
The ability to create a supersolid from light opens up exciting new avenues in both fundamental physics and applied technology. Some of the most promising implications include:
- Quantum Computing and Information Processing: Supersolids offer a unique platform for manipulating quantum states, which could lead to advancements in quantum computing. More stable and efficient qubits (the fundamental units of quantum computers) could be developed using this new form of matter.
- Advanced Optical and Photonic Devices: Since light is integral to modern communication and optical technologies, controlling it in a supersolid state may lead to improvements in optical processing, laser technologies, and next-generation photonic devices.
- Superconductors and Frictionless Materials: The frictionless flow observed in supersolids could inspire the development of new materials with zero resistance, improving energy efficiency in electronic and transportation systems.
- Precision Measurement and Sensing: Supersolids exhibit heightened sensitivity to external stimuli, making them ideal candidates for high-precision sensors in fields such as astrophysics, nanotechnology, and medical diagnostics.
The discovery that light can be converted into a supersolid represents a major leap in our understanding of quantum mechanics and opens doors to innovative technologies. By simplifying the study of supersolids and removing the need for ultracold atomic gases, this breakthrough sets the stage for practical applications that could revolutionize quantum computing, optical systems, and materials science. As researchers continue to explore the potential of photonic supersolids, we may uncover even more groundbreaking insights into the fundamental nature of matter and energy.