Details

Autor(en) / Beteiligte

• Kupfer, R.
• Quevedo, H. J.
• Smith, H. L.
• Lisi, L. A.
• Tiwari, G.
• Richmond, C. G.
• Bowers, B. B.
• Fang, L.
• Hegelich, B. M.

Titel

Cascade random-quasi-phase-matched harmonic generation in polycrystalline ZnSe

Ist Teil von

• Journal of applied physics, 2018-12, Vol.124 (24)

Ort / Verlag

Melville: American Institute of Physics

Erscheinungsjahr

2018

Link zum Volltext

Quelle

AIP - American Institute of Physics : Revues

Beschreibungen/Notizen

• We experimentally and numerically investigated the cascade random-quasi-phase-matched harmonic generation in polycrystalline zinc selenide with tightly focused mid-infrared nanosecond laser pulses. We observed a sharp transition between two distinct intensity scaling regimes as a function of pump energy from sub IN to super IN, where I is the pump intensity and N is the harmonic order. To gain an understanding of the observations of this complex nonlinear process, we carried out simulations of the coupled three-wave mixing equations with random grain sizes and orientations. We found a grain size dependence of the effective phase-matching condition, suggesting that manipulation of grain size can be an effective pathway to phase-matching optimization. This approach may provide a framework for effectively enhancing high harmonic generation and other wave mixing effects in polycrystalline materials.