Vertical Bridgman growth and low temperature luminescence properties of NaY(MoO4)2 crystal

Abstract NaY(MoO 4 ) 2 crystal was investigated as a promising scintillator for neutrinoless double beta decay experiment. In this study, NaY(MoO 4 ) 2 crystal was grown by the Vertical Bridgman method using spontaneous crystallization. The as-grown NaY(MoO 4 ) 2 crystal appeared dark blue in color. The powder X-Ray Diffraction, optical transmission spectra at room temperature, luminescence properties and decay time from room temperature to 10 K excited by a 280 nm light emitting diode source were investigated. The transmittance of the annealed NaY(MoO 4 ) 2 crystal sample with the thickness of 3 mm was about 80%. The NaY(MoO 4 ) 2 crystal did not luminescence from room temperature to 200 K and the emission spectra were observed down from 175 K. With the temperature decreasing, the luminescence light yield increased and had maximum peak at 10 K. Compared to Li 2 MoO 4 crystal, the luminescence light yield of NaY(MoO 4 ) 2 was much higher at 10 K. The longest average decay time was observed at 10 K (425 μs) and the shortest average decay time was observed at 175 K (88 μs). NaY(MoO 4 ) 2 crystal has a higher light yield at cryogenic temperature and no any heavy elements, so it is a promising candidate as a cryogenic detector for investigating the neutrinoless double-beta decay (0υββ) mechanism.