Engineerable generation of quadratic solitons in synthetic phase matching

Engineering of multicolor spatial solitons with chirped-period quasi-phase-matching gratings in optical parametric amplification

We demonstrate the excitation of solitons in a parametric amplifier with enhanced signal content through the use of a chirped-period quasi-phase-matching grating. This technique affords a low soliton threshold at the input end of a parametric amplifier, and the subsequent transformation to a desired soliton that exists at nonzero wave-vector mismatch through the use of a linearly chirped quasi-phase-matching grating. This approach has an advantage over direct excitation of solitons at nonzero wave-vector mismatch in uniform nonlinear materials and holds potential for improving the efficiency and mode quality of high-gain parametric amplifiers.

Frequency shifting with local nonlinearity management in nonuniformly poled quadratic nonlinear materials

We show theoretically that the frequency shifts that result from phase-mismatched cascaded processes under conditions of strong group-velocity mismatch can be significantly enhanced by local control of the nonlinearity with propagation. This control is possible with continuous variation of the poling period of quasi-phase-matched structures and can allow one to avoid saturation of the frequency shift. We theoretically demonstrate its applicability to high-quality, efficient frequency shifting of infrared pulses.

One-dimensional spatial soliton families in optimally engineered quasi-phase-matched lithium niobate waveguides

The advantage for quadratic soliton generation of engineering the quasi-phase-matching period near the input of lithium niobate slab waveguides is demonstrated. This approach allows members of one-dimensional quadratic soliton families with different values of the wave-vector mismatch to be cleanly excited and to be characterized by quantitative intensity-profile measurements of both the fundamental and the second-harmonic soliton components.