Investigation of ion-ion (Nd–Nd) interaction mechanisms in Sr3LaNb3O12:Nd3+ crystals

Abstract

The spectral-kinetic characteristics of Nd3+ optical centers (A, B, C centers) in Sr3LaNb3O12 crystals are studied by selective laser spectroscopy technique. It is found that the luminescence decay of A centers (donors) at the first stage is quenched by an ordered ensemble of acceptors (B centers) while the second stage is disordered and follows the Förster law.The macro-(γ(N1) = 55 cm−1/2, γ(N2) = 95 cm−1/2) and microparameters (CDA = 4.5⋅10−40 cm6/s) of the ion–ion (Nd3+–Nd3+) interaction are calculated using the static quenching theory. The closest distance between neodymium ions involved into the ion–ion (A and B optical centers) interaction is calculated to be Rmin. = 0.45 nm, and the boundary time at which the ordered luminescence quenching stage changes for disordered one is determined as tbound. ∼19 μs. It is shown that the A centers luminescence quenching mechanism is the dipole–dipole (S = 6) one.The Nd3+ luminescence build-up and decay kinetics in ensemble of acceptor centers (B centers) in case of unequal donor and acceptor lifetimes (τD <τA) are determined.