Term: harmonic frequency generation
https://doi.org/10.1351/goldbook.H02744

Definition:
Production of coherent radiation of frequency kν(k = 2, 3, ...) from coherent radiation of frequency. In general, this effect is obtained through the interaction of laser light with a suitable optical medium with non-linear polarizability. The case k = 2 is referred to as frequency doubling, k = 3 is frequency tripling and k = 4 is frequency quadrupling. Even higher integer values of k are possible.

Related Terms:
1) coherent radiation (http://doi.org/10.1351/goldbook.C01130).
2) laser (http://doi.org/10.1351/goldbook.L03459).
3) polarizability (http://doi.org/10.1351/goldbook.P04711).
4) frequency doubling (http://doi.org/10.1351/goldbook.F02527).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2245 (https://doi.org/10.1351/pac199668122223)

Citation: 'harmonic frequency generation' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.H02744

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