Helium-3

Error creating thumbnail:

Phase_diagram_of_helium-3_(1975)_0.002_K_region-en.svg

Helium-3 (He-3) is a light, stable isotope of helium with two protons and one neutron. It is rare on Earth but is more abundant on the Moon and in the gas giants of the Solar System. Helium-3 has potential applications in nuclear fusion, cryogenics, and neutron detection.

Properties

Helium-3 is a non-radioactive isotope of helium. It has a nuclear spin of 1/2, making it useful in quantum mechanics and low-temperature physics. The isotope has a lower boiling point than helium-4, which makes it valuable in cryogenics for achieving temperatures close to absolute zero.

Sources

On Earth, helium-3 is primarily obtained from the decay of tritium, a radioactive isotope of hydrogen. It is also found in trace amounts in natural gas deposits. The Moon's surface contains higher concentrations of helium-3, embedded in the regolith by the solar wind.

Applications

Nuclear Fusion

Helium-3 is considered a potential fuel for nuclear fusion reactors. Fusion of helium-3 with deuterium or another helium-3 atom produces a large amount of energy and fewer neutrons compared to the deuterium-tritium fusion reaction, making it a cleaner alternative.

Cryogenics

Due to its low boiling point, helium-3 is used in dilution refrigerators to reach temperatures below 0.3 kelvin. These refrigerators are essential for experiments in condensed matter physics and quantum computing.

Neutron Detection

Helium-3 is used in neutron detection equipment, such as neutron counters and neutron spectrometers. It is highly efficient at capturing neutrons, making it valuable for nuclear security and scientific research.

Challenges

The primary challenge in using helium-3 is its scarcity and high cost. Extracting helium-3 from the Moon or other extraterrestrial sources would require significant technological advancements and investment.

Future Prospects

Research is ongoing to develop practical methods for helium-3 extraction and utilization. If successful, helium-3 could play a crucial role in future energy production and scientific advancements.

See Also

• Helium
• Isotopes of helium
• Nuclear fusion
• Cryogenics
• Neutron detection