Lattice confinement fusion
Lattice confinement fusion (LCF) is a type of
History
In 2020, a team of NASA researchers seeking a new energy source for deep-space exploration missions published the first paper describing a method for triggering nuclear fusion in the space between the atoms of a metal solid, an example of screened fusion.[3] The experiments did not produce self-sustaining reactions, and the electron source itself was energetically expensive.[1]
Technique
The reaction is fueled with deuterium, a widely available non-radioactive hydrogen isotope composed of one proton, one neutron, and one electron. The deuterium is confined in the space between the atoms of a metal solid such as erbium or titanium. Erbium can indefinitely maintain 1023 cm−3 deuterium atoms (deuterons) at room temperature. The deuteron-saturated metal forms an overall neutral plasma. [dubious ] The electron density of the metal reduces the likelihood that two deuterium nuclei will repel each other as they get closer together.[1]
A
Although the lattice is notionally at room temperature, LCF creates an energetic environment inside the lattice where individual atoms achieve fusion-level energies.[3] Heated regions are created at the micrometer scale.
Screened fusion
The energetic deuteron fuses with another deuteron, yielding either a 3helium nucleus and a neutron or a 3hydrogen nucleus and a proton. These fusion products may fuse with other deuterons, creating an alpha particle, or with another 3helium or 3hydrogen nucleus. Each releases energy, continuing the process.[1]
Stripping reaction
In a stripping reaction, the metal strips a neutron from accelerated deuteron and fuses it with the metal, yielding a different isotope of the metal.[1] If the produced metal isotope is radioactive, it may decay into another element, releasing energy in the form of ionizing radiation in the process.
Palladium-silver
A related technique pumps deuterium gas through the wall of a palladium-silver alloy tubing. The palladium is electrolytically loaded with deuterium. In some experiments this produces fast neutrons that trigger further reactions.[1] Other experimenters (Fralick et al.) also made claims of anomalous heat produced by this system.
Comparison to other fusion techniques
Pyroelectric fusion has previously been observed in erbium hydrides. A high-energy beam of deuterium ions generated by pyroelectric crystals was directed at a stationary, room-temperature ErD2 or ErT2 target, and fusion was observed.[2]
In previous fusion research, such as
Lattice confinement fusion requires energetic deuterons and is therefore not cold fusion.[1]
Lattice confinement fusion is used as a method to increase the cathode fuel density of inertial electrostatic fusion devices such as a Farnsworth-Hirsch fusor. This increases the probability of fusion events occurring and therefore the radiation output produced. In applications where fusors are used as X-ray, neutron, or proton radiation source, lattice confinement fusion improves the energy efficiency of the device. [citation needed]
See also
- Inertial confinement fusion
- Magnetized target fusion
- Pyroelectric fusion
- Inertial electrostatic confinement
References
- ^ a b c d e f g h Baramsai, Bayardadrakh; Benyo, Theresa; Forsley, Lawrence; Steinetz, Bruce (February 27, 2022). "NASA's New Shortcut to Fusion Power". IEEE Spectrum.
- ^ S2CID 219083603– via APS.
- ^ NASA Glenn Research Center. Retrieved March 1, 2022. This article incorporates text from this source, which is in the public domain.