Highly spin-polarized deuterium atoms from the UV dissociation of Deuterium Iodide

Abstract

We report the production of highly spin-polarized Deuterium atoms via photodissociation of deuterium iodide at 270 nm. The velocity distribution of both the deuterium and iodine photodissociation products is performed via velocity mapping slice-imaging. Additionally, the angular momentum polarization of the iodine products is studied using polarization-sensitive ionization schemes. The results are consistent with excitation of the $A^1Π_1$ state followed by adiabatic dissociation. The process produces $\sim$100\% electronically polarized deuterium atoms at the time of dissociation, which is then converted to $\sim 60\%$ nuclear D polarization after $\sim 1.6$ ns. These production times for hyperpolarized deuterium allow collision-limited densities of $\sim 10^{18}$ cm$^{-3}$, which is $\sim 10^6$ times higher than conventional (Stern-Gerlach separation) methods. We discuss how such high-density hyperpolarized deuterium atoms can be combined with laser fusion to measure polarized D-D fusion cross sections.