We report on the development of scintillating bolometers based on lithium
molybdate crystals containing molybdenum depleted in the double-β active
isotope 100Mo (Li2100deplMoO4). We used two
Li2100deplMoO4 cubic samples, 45 mm side and 0.28 kg each,
produced following purification and crystallization protocols developed for
double-β search experiments with 100Mo-enriched Li2MoO4
crystals. Bolometric Ge detectors were utilized to register scintillation
photons emitted by the Li2100deplMoO4 crystal
scintillators. The measurements were performed in the CROSS cryogenic set-up at
the Canfranc underground laboratory (Spain). We observed that the
Li2100deplMoO4 scintillating bolometers are characterized
by excellent spectrometric performance (∼3--6 keV FWHM at 0.24--2.6 MeV
γ's), moderate scintillation signal (∼0.3--0.6 keV/MeV depending on
light collection conditions) and high radiopurity (228Th and 226Ra
activities are below a few μBq/kg), comparable to the best reported results
of low-temperature detectors based on Li2MoO4 with natural or
100Mo-enriched molybdenum content. Prospects of
Li2100deplMoO4 bolometers for use in rare-event search
experiments are briefly discussed.Comment: Prepared for submission to MDPI Sensors; 16 pages, 7 figures, and 3
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