Quantum Leap: Physicists Achieve Reversible Superfluid-to-Supersolid Transition for the First Time

United States - Ekhbary News Agency

Quantum Leap: Physicists Achieve Reversible Superfluid-to-Supersolid Transition for the First Time

In a groundbreaking advancement that pushes the boundaries of quantum mechanics and condensed matter physics, an international team of physicists has successfully observed a reversible phase transition from a superfluid to a supersolid state, and back again. This unprecedented achievement, detailed in a recent study published in the prestigious journal Nature on January 28, marks the first time such a natural and reversible transformation has been witnessed, specifically involving a type of quasiparticle known as excitons. The discovery opens entirely new avenues for understanding and manipulating exotic states of matter under extreme conditions, potentially revolutionizing fields from quantum computing to fundamental physics research.

The research team's breakthrough centers on excitons, fascinating quasiparticles formed when an electron and an electron hole are bound together. By meticulously controlling environmental conditions, scientists were able to guide these excitons through a sequence of phase changes that defy conventional understanding of matter. While the existence of superfluids and supersolids has been theorized and, in some cases, experimentally created, the ability to induce a spontaneous and reversible transition between these two highly unusual states represents a significant leap forward. This is akin to observing water spontaneously freeze into ice and then melt back into liquid, but at the quantum level with far more complex properties.

To appreciate the magnitude of this discovery, it is essential to understand superfluids and supersolids. Superfluids are a state of matter that emerges when certain particles, such as helium isotopes or excitons, are cooled to temperatures just above absolute zero – the point at which all atomic motion ceases. Unlike conventional liquids, superfluids exhibit zero viscosity, meaning they can flow without any resistance from friction. When stirred, they form persistent, microscopic vortices known as quantum vortices, a testament to their peculiar quantum mechanical properties. They are, in essence, frictionless liquids capable of seemingly defying gravity and flowing indefinitely.

Supersolids, on the other hand, are an even more enigmatic state of matter. Theorized to exist when superfluids are cooled even further, they possess the frictionless flow characteristic of superfluids but also exhibit a rigid, orderly structure, much like a crystalline solid. Imagine a material that is both a perfect fluid and a perfect crystal simultaneously – a concept that challenges intuitive understanding. Prior to this study, supersolids had been created in laboratories, notably with dysprosium atoms in 2021 and through the observation of quantum vortices in a supersolid in 2024. However, these previous experiments typically relied on external equipment and energy to coerce particles into an orderly lattice, effectively forcing the supersolid state. The new research stands apart by demonstrating a natural, spontaneous phase transition.

"For the first time, we've seen a superfluid undergo a phase transition to become what appears to be a supersolid," stated Cory Dean, a physicist at Columbia University and a co-author of the seminal study. This observation is crucial because it suggests a fundamental mechanism for the formation of supersolids that does not require external scaffolding, validating long-standing theoretical predictions.

The experimental setup involved a remarkably simple yet ingenious design. Researchers placed two ultra-thin sheets of graphene – a material composed of a single layer of carbon atoms – in extremely close proximity. A powerful magnetic field was then applied, and the entire system was cooled to create a "soup" of excitons. As the temperature was precisely lowered to between 2.7 and 7.2 degrees Fahrenheit (1.5 to 4 degrees Celsius) above absolute zero, the excitons coalesced into a superfluid. Crucially, when the system was cooled even further, the excitons transformed into an electrically insulative, mysterious new phase, which the research team strongly suspects is the theorized supersolid state. The ability to reverse this process by slightly warming the system further solidified their conclusions.

This discovery holds profound implications for fundamental physics. It provides a robust platform for studying the interplay between quantum mechanics, thermodynamics, and material structure in extreme environments. Furthermore, understanding how these exotic states transition naturally could pave the way for novel technological applications. For instance, the frictionless flow of superfluids and supersolids could inspire new approaches to energy transmission or quantum computing, where minimizing dissipation is paramount. The natural and reversible nature of this transition offers a new lens through which scientists can explore the complex landscapes of quantum matter, potentially revealing entirely new phenomena and properties yet to be imagined.

Ekhbary News Agency