Diode-pumped two-frequency lasers based on c-cut vanadate crystals

The luminescent and lasing properties of the neo-dymium ion at the ⁴F_3/2—⁴I_11/2 transition in c-cut vanadate crystals (Nd:YVO₄, Nd:GdVO₄, and Nd:Gd_1-xY_xVO₄) are studied. Tuning of the laser radiation wavelength (Δλ = 5.4 nm) is demonstrated. Two-frequency laser schemes with the use of a Lyot filter, a Fabry–Perot etalon, and a Brewster prism as spectral selection elements are proposed and experimentally realised. Stable two-frequency lasing of a laser based on the c-cut Nd:GdVO₄ crystal was obtained in the cw, Q-switched (nanosecond pulses), and active acousto-optic mode-locked (picosecond pulses) regimes.