Optical properties of the Czochralski grown Cs₂MoO₄ crystal

Single crystal growth of novel dicesium molybdate (Cs₂MoO₄) crystal by Czochralski technique was carried out. The single crystal phase was confirmed by powders X-ray diffraction analysis. The optical band gap of 4.22 eV was estimated from the absorbance spectra, measured at room temperature. The luminescence properties were measured under the excitation of 4.42 eV UV light from an LED source in the temperature range of 10–300 K. The photoluminescence light yield increases upon cooling down the grown crystal to 10 K. The luminescence decay time was analyzed with the sum of three exponential decay-time functions in the entire temperature range. The comparison of luminescence light yield with Li₂MoO₄ (one of the promising scintillating bolometers for the neutrinoless double-beta decay search) at 10 K shows a similar light output. These preliminary investigations show that the grown crystal can be a good candidate crystal for the cryogenic dark matter and neutrinoless double-beta decay search.