What Is a Nuclear Laser?

A nuclear laser is a device proposed by physicists in 2011 based on the stimulation of atomic nuclei to produce light, instead of electrons like other types of lasers. It may allow for extremely accurate tests of the laws of physics and properties of nature, without emitting gamma rays. The laser will emit light by exciting enough nuclei in a sample; the change in state created either by a strong magnetic field or a powerful and dense gradient in the electrical field within the device. By using a nuclear laser, researchers are working to develop a new way to analyze frequencies or make a precise nuclear clock.

For a nuclear laser to work, the atomic nuclei need to remain in an excited state for a long period of time. A substance called thorium has the properties that are sufficient to achieve this. An electric or magnetic field could interact with a compound made of lithium-calcium-aluminum-fluoride. Thorium would be added to the compound in place of some of the calcium atoms. The electric or magnetic field would be used to change the state of the atomic nuclei in a process called a population inversion.

Nuclear technology has been used to develop functional plans for how a nuclear laser would operate. In a nuclear pumped laser, the energy stored in atomic nuclei is converted into the laser beam. Specific wavelengths of light can also be produced through the generation of plasmas based on the principles of nuclear fission. Excited nuclei split to produce energy in the laser mechanism, the principle behind creating the light for the laser beam. An optical system with mirrors further modifies the light so that it is concentrated into the beam, enabling the device to be used in scientific applications.

Lasers have been used since the 1960s. The common types of gas laser use gases such as helium-neon, carbon dioxide, or argon, and combine them with electricity to generate light. Other lasers combine gas with chemicals, but a nuclear laser would theoretically use energy from the nucleus of an atom to create light. One problem is to get one nucleus to cause another to become active, so the photons that interact with them must be focused at a proper frequency. In creating any new technology, physicists need to study various atomic principles, including laws that describe how atomic particles interact in different ways, and apply the appropriate ones to their designs.