1.3-μm emission of Nd:LaF3 thin films grown by molecular beam epitaxy

The 1.3-mu m emission of Nd3+-doped LaF3 thin films grown on LaF3 acid CaF2 (111) substrates by molecular beam epitaxy is reported. The waveguide behavior of the heteroepitaxial layers has been demonstrated and the refractive indexes measured. Guided spectra have been obtained from these layers using a prism-coupling technique. The 1.3-mu m emission corresponding to the F-4(3/2)-->I-4(3/2) transition has been characterized as a function of Nd3+ concentration and temperature. The relative efficiencies of different excitation bands were compared. The optimum concentration for Nd3+ dopant has been found to be about 1 at.%, A narrowing of the emission lines is observed in the homoepitaxial layers compared to the heteroepitaxial layers, The decay of the luminescence of the F-4(3/2) level measured at room temperature is similar for homoepitaxial and heteroepitaxial layers.