We report on a widely-tunable mid-infrared picosecond optical vortex laser source that employs a synchronously-pumped optical parametric oscillator optimized for mid-infrared emission up to 5 μm. Vortex output with a continuously-tunable wavelength range of 2.6–5 μm could be obtained simply by translating the MgO:PPLN crystal. At the maximum pump power of 15 W, the maximum idler output powers were measured as 3.7, 1.7, and 0.165 W at the wavelengths of 2.6, 3.8, and 5 μm, respectively. The corresponding photon conversion efficiencies were estimated to be 60% at 2.6 μm, 40% at 3.8 μm, and 5.2% at 5 μm.

In this paper, we present a picosecond pulsed, synchronously pumped optical parametric oscillator producing vortex beam output with tunable wavelengths in the near- to mid-infrared range. The system utilizes a Nd:YVO₄ picosecond pulsed solid-state laser emitting at a wavelength of 1.064 µm to pump a Z-shaped, singly resonant OPO which contains a MgO:PPLN crystal with a fan-shaped grating. The wavelength tuning characteristics of the OPO output are examined both as a function of the MgO:PPLN grating period and crystal temperature. The orbital angular momentum of the pump field can be selectively transferred to either the signal or idler fields by appropriately adjusting the location of the MgO:PPLN crystal within the OPO cavity. The maximum output power of the signal and idler vortex fields are 5.12 W and 3.46 W, respectively, for an incident pump power of 19 W.

We present a high-power, widely tunable, synchronously pumped picosecond pulsed optical parametric oscillator (OPO) generating emissions in the near to mid-infrared wavelength ranges. The OPO is pumped using a Nd:YVO₄ picosecond pulsed laser and utilizes a fan-shaped, multi-grating MgO doped PPLN crystal (MgO:PPLN). The system generates near to mid-infrared output across the wavelength range 1.3–5 µm, with a high overall conversion efficiency of 75.15%.