Study of optical and luminescent properties of nanocrystals NaYF4:Tm3+, Yb3+ in the UV range in the application of integrated opticsI.M. Asharchuk, S.I. Molchanova, V.V. Rocheva, M.S. Baranov, M.E. Sarycheva and K.V. KhaydukovEPJ Web Conf., 132 (2017) 03002DOI: https://doi.org/10.1051/epjconf/201713203002