When helium, best known for its usage in balloons and as a cryogenic agent, is pushed to extremely high temperatures and pressures, it displays surprising qualities. Helium is typically found in its gaseous form, but it can also exist in a solid state provided the right conditions are met. In this piece, we explore the fascinating world of solid helium and explain some of its peculiar properties.
What is Solid Helium
At very low temperatures and very high pressures, helium changes into a solid state known as solid helium. Helium changes from its usual gaseous state into a solid substance when cooled to temperatures below 2.17 Kelvin (-270.98 degrees Celsius or -455.76 degrees Fahrenheit) and exposed to enormous pressure.
Quantum Behavior
Due of the low temperatures at which solid helium originates, it displays quantum characteristics. Interesting quantum effects manifest themselves at very low temperatures. In the solid state, helium atoms function as quantum particles, exhibiting wave-like behaviors and behaving as a group rather than as independent entities.
Superfluidity
Superfluidity is one of the most fascinating properties of solid heliu’m. When a substance, at temperatures very close to absolute zero, flows without resistance or friction, this is known as superfluidity. Because of their quantum nature, helium atoms can move collectively in solid helium, resulting in a frictionless flow. Researchers are still digging deep into the mysteries of this peculiar behavior.
Helium-3 and Helium-4
There are two stable isotopes of helium in the solid state: helium-3 and helium-4. At temperatures below 2.17 Kelvin, the more common isotope of helium, helium-4, becomes superfluid. It passes through a phase change into a superfluid form called helium-II, which possesses unique abilities like zero viscosity and the capacity to scale vertical surfaces against the pull of gravity. While helium-3 does not show signs of superfluidity at these temperatures, it does have some other fascinating properties.
Quantum Crystalline State
It is possible to achieve a quantum crystalline state in helium-4 at even lower temperatures and higher pressures. Here, the helium atoms self-organize into a crystal lattice while still keeping their quantum features. This new solid helium material has caused quite a stir in the scientific community since it defies commonplace assumptions about crystalline behavior.
Exotic Properties
There are many additional fascinating characteristics that solid heliu’m displays. In one example, it shows that helium atoms can “quantum tunnel” over energy barriers that would be insurmountable using only conventional physics. Further, when subjected to magnetic fields, solid helium exhibits a unique response that reveals quantum-level interactions between the heliu’m atoms.
Conclusion
An intriguing intersection of quantum physics, low-temperature physics, and condensed-matter physics, solid heliu’m is a fascinating area of research. Because of its unusual characteristics, including as superfluidity and the quantum crystalline state, it continues to pose a formidable challenge to our knowledge of the underlying structure of matter and to fascinate scientists. Superconductivity and quantum computing are only two of the domains that could benefit from our increased understanding of the quantum world that comes with exploring the secrets of solid heliu’m. More exciting findings are likely to emerge as this field of study develops.
FAQs
What is solid helium?
At very low temperatures and high pressures, helium changes into its solid state, known as solid heliu’m. It is a type of helium that, when chilled to temperatures below 2.17 Kelvin (-270.98 degrees Celsius or -455.76 degrees Fahrenheit), changes from a gas to a solid.
How is solid helium different from regular helium?
At standard conditions, helium exists in the gaseous state. However, helium can be solidified into a substance with its own set of properties by being exposed to extremely low temperatures and high pressure.
What are the properties of solid heliu’m?
Since solid heliu’m only forms at extremely low temperatures, it displays quantum behavior. At temperatures very close to absolute zero, it is superfluid, meaning it flows without resistance. Quantum crystalline heliu’m is a phase of solid heliu’m in which the heliu’m atoms arrange themselves in a crystal lattice while still preserving their quantum characteristics.
What is superfluidity in solid heliu‘m?
The amazing attribute of superfluidity of solid heliu’m is its lack of viscosity and resistance to flow. The helium isotope helium-4 becomes the superfluid helium-II at temperatures below 2.17 Kelvin. Amazing phenomena, such as the ability to scale walls defying gravity and flow through minuscule channels, are displayed by this superfluid helium-II.
Can helium-3 form a superfluid state?
When cooled to temperatures below 2.17 K, helium-3, another helium isotope, does not show signs of superfluidity. But it’s got its own quirks and can change phases at even lower temperatures and higher pressures than usual.