Thermal Characteristics of Lithium Indium Diselenide and Lithium Indium Gallium Diselenide Neutron Detection Crystals

Tracking special nuclear materials (SNM) has never been more important than in the 21^st century where information is transferred rapidly around the globe. Tracking SNM is important to nuclear power, weapons, medicine, and science. Neutron and gamma ray detection are the primary methods of detecting SNM. Increased movement and availability of SNM have increased the demand for radiation detection systems beyond the capacity of traditional neutron detection technologies (³He) [Helium three]. Many alternative neutron detection materials are being considered, including ⁶LiInSe₂ [Lithium Indium Diselenide grown with lithium enriched in lithium six] and its derivative ⁶LiIn_1-xGa_xSe₂ [Lithium Indium Gallium Diselenide: where the x represents varying concentrations of each constituent]. The research herein describes thermal transport and expansion properties of these materials to help better inform both crystal growers and detection designers. While preliminary reports indicate promising detection properties, improvements in crystal size and quality are required to improve neutron detection charge collection efficiency for nonproliferation applications.