Abstract

Using Nd³⁺ as the active ion and yttrium orthosilicate (Y₂SiO₅) as the host material, efficient Q-switched laser operation has been demonstrated on the Nd^{3+ 4}F_3/2 – ⁴I_9/2 transition. Figure 1 shows the detailed Stark splittings of the ⁴F_3/2 and ⁴I_9/2 manifolds for both reported types of optical center Nd³⁺ occupies.¹ Because the lasing transition terminates on a Stark level only 355 cm⁻¹ above the lowest lying ⁴I_9/2 level, a 10% excited state fraction is required just to obtain 912-nm transparency, and substantial bleaching is required before efficient Q-switched laser operation is possible.

© 1990 Optical Society of America