Alan Hill Created 2026-10-18 Updated 2026-11-05
Alan Hill, credited as A. E. Hill, coauthored the 1961 observation of optical harmonic generation. A sufficiently intense optical field drives a nonlinear material response, producing light at a multiple of the incident frequency.
The experiment connected nonlinear polarization with a measured new spectral component, helping establish experimental nonlinear optics. The source author list is the verified attribution; no unverified personal dates or appointments are added.[ref]
Generation of Optical Harmonics by Peter Alden Franken and others. 1961, author list and reported harmonic-generation experiment
C. Wilbur Peters Created 2026-10-18 Updated 2026-11-05
An experimental optical physicist who coauthored a 1961 observation of optical second-harmonic generation. Passing intense laser light through quartz generated radiation with half the incident wavelength. Spectral separation of that weak new component supplied a direct test of the optical medium's nonlinear polarization.[ref]
Franken and colleagues frequency-doubling experiment Created 2026-10-18 Updated 2026-10-20
In 1961, Peter Alden Franken, Alan Hill, C. Wilbur Peters and Gabriel Weinreich focused a pulsed ruby laser through a red optical filter into quartz. The filter suppressed xenon-flash background. A quartz-prism spectrograph used red-insensitive Eastman Type 103 plates. A single shot recorded a feature near from input. Removing the quartz or substituting glass removed the feature; changing polarization of waves and orientation followed their predicted pattern. These controls supported second-harmonic generation; photographic density gave an estimated yield.[ref]
Generation of Optical Harmonics by Peter Alden Franken and others. pp. 118–119, Table I, Fig. 1 and controls
A spectrograph turns output frequency into a recording position. Its spectral separation makes a faint new component distinguishable from bright input light. The reported rounded wavelengths do not constitute an independent precision measurement of the ratio two. Nor do these observations demonstrate perfect phase matching or complete conversion. The experiment and Nicolaas Bloembergen's later theoretical account are distinct contributions to nonlinear optics.
Gabriel Weinreich Created 2026-10-18 Updated 2026-11-05
An experimental optical physicist who coauthored the observation of optical second-harmonic generation. A strong ruby-laser pulse passing through quartz produced light at twice the incident frequency. The experiment showed that a material's nonlinear polarization could mix an optical field with itself, turning a nonlinear response into a new observable color.[ref]
Generation of Optical Harmonics by Peter Alden Franken and others. 1961 report: ruby laser, quartz and doubled optical frequency
Peter Alden Franken Created 2026-10-18 Updated 2026-11-05
Peter Alden Franken coauthored the 1961 observation of optical second-harmonic generation. Intense ruby-laser light passing through quartz produced radiation at twice the incident frequency. A quadratic contribution to nonlinear polarization explains why this is possible: squaring a sinusoidal electric field produces a term at twice its frequency. The experiment made frequency conversion a measured consequence of nonlinear material response.[ref]
Generation of Optical Harmonics by Peter Alden Franken and others. 1961 original report, ruby-laser illumination of quartz and frequency-doubled radiation; quadratic-response interpretation
Portrait of Peter Alden Franken
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