Consecutive parametric interactions of light waves with aliquant frequencies

Broadband noncollinear optical parametric amplification under low‐frequency picosecond pump in homogeneous KTP crystal

“…The fact that UV light is obtained with a phase mismatch does not matter, because the “carrier of the phase” now is the pair “pump(ω p )&signal(ω s ),” which generates at each point of each thin layer L abs a new pump wave with regular phase that leads to constructive interference of “blue light” waves along path length. In some sense, it looks like a quasi‐phase‐matched process with spatial modulation of the nonlinearity: every thin layer L abs works as a short nonlinear crystal with a new pump wave (UV light, λ UV ~300 nm) at the input and with a new signal (“blue light,” λ aS ~460 nm) together with a “new idler” (“idler2,” λ idler2 ~870 nm) waves at the output. The last proof of the correctness of our interpretation of the “blue light” is the presence at the NOPA output of near infrared emission: we managed to register the spectra in the region of 860–890 nm, and we attribute them to the emission of the new idler wave.…”

“…The wavevector mismatch for a few simultaneous parametric processes can be minimized due to QPM interactions; therefore, quadratic cascading is usually implemented in periodically poled nonlinear materials . In the presence of the quadratic cascading, the parametric amplification under a low‐frequency pump (PALFP), that is, amplification of the signal wave by a coherent pump wave of lower frequency, is possible too . Because concurrent execution of the phasematching is needed for a few parametrical processes, QPM materials are usually used for PALFP.…”

“…[9] In the presence of the quadratic cascading, the parametric amplification under a low-frequency pump (PALFP), that is, amplification of the signal wave by a coherent pump wave of lower frequency, is possible too. [10][11][12] Because concurrent execution of the phasematching is needed for a few parametrical processes, QPM materials are usually used for PALFP.…”

Multistep parametric processes in nonlinear optics

“…Plane-wave single-pass theory of the new frequency generation with OPO with the simultaneous frequency doubling of the signal wave in the OPO crystal was presented in Aytur and Dikmelik [1998]. The case of OPO with the simultaneous frequency mixing between the pump and signal waves -in Dikmelik, Akgun, and and Morozov and Chirkin [2003]. Moore, Koch, Dearborn, and Vaidyanathan [1998] considered theoretically the simultaneous phased matched tandem of OPOs in a single nonlinear crystal.…”