Scattering-free Ce:LYBO single crystals for thermal neutron detection

Abstract

Ce:Li6Y(BO3)3 (LYBO) is a well-known candidate for thermal neutron detection with a very high Li concentration (3.06 × 1022/cm3). So far, as-grown crystals exhibit a milky appearance that compromises their performance as scintillators. Current work demonstrates, for the first time, the growth of scattering-free undoped and Ce-doped LYBO by a thermal quenching process. The origin and features of the scattering centers are investigated in detail. Furthermore, the annealing treatment for the scintillation activation is studied, finding that the reduction in oxygen vacancies is mandatory. Under thermal neutron irradiation, the annealed scattering-free Ce:LYBO single crystal achieves a record-high light yield of 6200 ph/n in a single decay with a lifetime as short as 24 ns.