Spin‐polarized protons and deuterons in hydrogen‐isotope solids

New techniques for production of highly polarized H↑D, ↑D↑D and ↑D↑T solids in the ‘frozen‐spin’ mode have been conceived and are under investigation, spurred by their potential application as nuclear fusion fuels. The ↑D↑D methods are directly applicable to spin‐physics targets, and ↑H↑D targets superior to those previously described are expected from development of the new technique. The new techniques feature relaxation rate switching modes faster than the symmetry species conversion previously described (for example, radiation damage‐anneal cycles), and epitaxial deposition of molecular isotopic variants on metastably polarized ↑H↑D or ↑D↑D blocks at T=1−4K an in fractional Tesla holding fields, wherein spin diffusion produces high polarization in the deposited layer even in the presence of considerable heat generation from internal radiation or symmetry species conversion. Production of polarized ↑H↑D and ↑D↑D liquids appears feasible, as well as positively or negatively charged ↑H, ↑D and ↑T beams f...