Effect of confinement on the Eu3+ emission band 5D0→7F0 in Eu3+-doped nano-glass-ceramics

We report a non-linear blue shift of the zero-phonon emission line 5D0→7F0 of Eu3+-dopant in Eu3+-doped nano-glass-ceramics in magnetic field up to 50 T. The shift is significantly larger in nano-glass-ceramics compared to its precursor glass, suggesting that the nanoceraming of the precursor glass decreases the effective mass of the f-electrons bands of Eu3+ resulting in their enhanced magnetic confinement. Moreover, the non-linear character of the magnetic field dependence of this blue energy shift denotes a spatial confinement of f-electrons wave-functions of Eu3+ dopants in the PbF2-based nanocrystals of the nano-glass-ceramics where up to 90% of the dopants partition. The spatial confinement seems to be due to an admixture to the f-states of Eu3+ of its higher lying states of opposite parity which fall in the quantum well comprising of Eu3+-doped PbF2 crystalline nanoparticles embedded in the surrounding glass network.