Li2MoO4 Crystals Grown by Low-Thermal-Gradient Czochralski Technique

For the first time Li 2 MoO 4 crystals, including samples enriched with isotope molybdenum-100 ( 100 Mo), were grown by Czochralski technique at low-thermal-gradient conditions (LTG Cz), which allowed obtaining crystals of record size and quality. Dependence between growth rate, growth mechanism and crystal faceting was established. Low temperature tests of the produced Li 2 MoO 4 and Li 2 100 MoO 4 scintillating bolometers have demonstrated high performance of the detectors in terms of energy resolution and particle discrimination ability. Radioactive contamination of the Li 2 MoO 4 and Li 2 100 MoO 4 crystal scintillators produced from selected initial materials after double crystallization was tested in low background underground conditions. The achieved radiopurity level satisfies the requirements of the next generation large scale double beta decay experiments.