Production of spin-controlled rare isotope beams

The degree of freedom of spin in quantum systems serves as an unparalleled laboratory where intriguing quantum physical properties can be observed, and the ability to control spin is a powerful tool in physics research. We propose a method for controlling spin in a system of rare isotopes which takes advantage of the mechanism of the projectile fragmentation reaction combined with the momentum-dispersion matching technique. The present method was verified in an experiment at the RIKEN RI Beam Factory, in which a degree of alignment of 8% was achieved for the spin of a rare isotope 32 Al. The figure of merit for the present method was found to be greater than that of the conventional method by a factor of more than 50. Enhanced control of the nuclear spin orientation of rare isotopes has now been demonstrated. This technique is considerably more efficient than traditional methods and significantly broadens the domain of accessible nuclei, promising insights in nuclear physics and applications in material science.