New Materials for Optical Frequency Conversion via Stimulated Raman Scattering and Cascaded χ ⁽³⁾ ↔ χ⁽²⁾ Processes

Abstract

Non-centrosymmetric, simultaneously χ ⁽²⁾ and χ ⁽³⁾ active crystals offer a large variety of possibilities for the generation of new coherent wavelengths of light. Frequency conversion processes such as stimulated Raman scattering (SRS), second harmonic generation (SHG) or sum and difference frequency mixing can be combined efficiently in one crystal in cascaded χ ⁽³⁾ ↔ χ ⁽²⁾ processes. An analysis of some cascaded χ ⁽³⁾ ↔ χ ⁽²⁾ processes is given using the examples of polar Li₂SO₄ · H₂O and non-centrosymmetric Y(HCOO)₃ · 2H₂O.

Keywords:

• Non-centrosymmetric crystals
• Y(HCOO)₃ · 2H₂O
• Li₂SO₄ · H₂O
• stimulated Raman scattering (SRS)
• cascaded χ⁽³⁾ ↔ χ⁽²⁾ processes

Acknowledgment

One of us (A.A.K.) is grateful to the Russian Foundation for Basic Research and the Russian Academy of Sciences for their support.