Аннотация:The simultaneous generation of stimulated radiation of Nd3+ ions and its second harmonic generation was observed in NYAB crystals. In the 0.05 to 0.35 mol.% Nd range, the emission can be generated by two transitions of the Nd3+: 4F3/2 →4I11/2 and 4F3/2 → 4I13/2 with wavelength =1.06 and =1.32 m, respectively. The lifetime of the ions in the excited 4F3/2 state (at x=0.2-0.3 mol.% Nd optimum concentration) is 45-40 s. NYAB crystals possess phase synchronism of the oo e type which permit frequency doubling for both laser transitions over the whole x composition range. The intensities of - and -luminescence components are almost the same. Therefore, for NYAB as an active-nonlinear medium, the difficulties connected with unfavorable luminescence polarization usually encountered for example, in LiNbO3:Nd3+, do not appear. The optically homogenous crystals withstand repeated radiation by laser pulses equal to 400-600 MWt/cm2 with =1.06 mm and ~ 10-8 s. The effect of induced optic inhomogeneity in them is not observed up to the damage threshold. The high concentration of active ions (1.08•1021 to 1.66•1021) enables the use of large amplification factors.