What is a Supersolid and how did Scientists turn Light into a Supersolid?

For the first time in history, researchers have successfully transformed light into a Supersolid—a unique state of matter that exhibits properties of both a solid and a liquid simultaneously. This breakthrough, published in the journal Science on March 5, marks a significant advancement in condensed-matter physics and quantum mechanics.

What is a Supersolid?

A supersolid is an extraordinary state of matter where particles arrange themselves in an orderly, crystalline solid structure while also exhibiting liquid-like movement without viscosity (internal friction). Unlike conventional solids, supersolids can change direction and density while maintaining their lattice structure.

What are the characteristics of a supersolid?

Supersolid consists of a dual nature with quantum coherence, zero viscosity, and temperature dependency. Here all its characteristics are given in detail:

• Dual Nature: Combines properties of solids and superfluids.
• Quantum Coherence: Particles exist in a highly correlated state due to quantum effects.
• Zero Viscosity: Moves without internal resistance.
• Temperature Dependency: Requires ultra-cold conditions close to absolute zero (-273.15°C).

Why Do Supersolids Require Extreme Cold?

Supersolids only form under extremely low temperatures, typically near absolute zero. At such low temperatures:

• Heat energy is minimised, preventing particles from moving chaotically.
• The effects of quantum mechanics dominate over classical physics.
• Particles condense into their lowest energy state, allowing researchers to study quantum interactions more effectively.

Analogy:

Imagine a ball pit filled with children. When they are active (at higher temperatures), it's chaotic. However, once they settle down (lower temperature), the system is more structured, allowing a better analysis of the interactions among the balls.

How Can a Fluid Have No Viscosity?

Viscosity measures how resistant a fluid is to motion. Most fluids, like water or syrup, have some level of viscosity. However, superfluids and supersolids exhibit zero viscosity, meaning they can move without friction.

Example: Superfluid Helium-4

• At temperatures near absolute zero, Helium-4 transitions into a superfluid.
• It stops experiencing friction, allowing it to flow without resistance.
• Helium-4 can even climb up container walls due to quantum effects.

How Did Scientists Turn Light into a Supersolid?

The Role of Polaritons

Unlike previous supersolids created from atomic gases, researchers used polariton systems—a unique combination of photons (light) and excitons (electron-hole pairs). Polaritons exhibit quantum properties similar to atomic gases, allowing them to form a supersolid state.

The Mechanism:

1. Photon-Matter Coupling: Strong electromagnetic interactions bind photons and quasiparticles.
2. Energy Condensation: The system reaches its lowest energy state, forming a supersolid.
3. Quantum Coherence: The polaritons maintain a structured lattice while behaving like a liquid.

Why is this discovery important?

The ability to create a supersolid from light has profound implications across multiple fields of science and technology.

Potential Applications:

Beyond these, this research paves the way for further discoveries in condensed matter physics and the development of futuristic technologies we have yet to conceive.

Conclusion

The transformation of light into a supersolid marks a groundbreaking achievement in physics. This discovery not only expands our knowledge of quantum matter but also opens doors for revolutionary advancements in quantum computing, superconductivity, and material science. As research progresses, the potential applications of supersolids will continue to grow, shaping the future of technology and scientific exploration.