We report on a novel experimental scheme to generate continuous-wave (cw),high power, and higher-order optical vortices tunable across mid-IR wavelengthrange. Using cw, two-crystal, singly resonant optical parametric oscillator(T-SRO) and pumping one of the crystals with Gaussian beam and the othercrystal with optical vortices of orders, lp = 1 to 6, we have directlytransferred the vortices at near-IR to the mid-IR wavelength range. The idlervortices of orders, li = 1 to 6, are tunable across 2276-3576 nm with a maximumoutput power of 6.8 W at order of, li = 1, for the pump power of 25 Wcorresponding to a near-IR vortex to mid-IR vortex conversion efficiency ashigh as 27.2%. Unlike the SROs generating optical vortices restricted to lowerorders due to the elevated operation threshold with pump vortex orders, here,the coherent energy coupling between the resonant signals of the crystals ofT-SRO facilitates the transfer of pump vortex of any order to the idlerwavelength without stringent operation threshold condition. The genericexperimental scheme can be used in any wavelength range across theelectromagnetic spectrum and in all time scales from cw to ultrafast regime.
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