Nonlinear dispersion of avalanche upconversion
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Updated: Jul 8, 2026

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Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
Optics Letters
|January 15, 1997
Abstract:
Two-beam coupling measurements of an avalanche upconversion transition in concentrated Tm:LiYF (4) confirm that, despite the resonant nature of the excited-state optical interaction, the induced response is strongly dispersive. This surprising characteristic is shown to be a general feature of avalanche polarization, with an off-resonant process dominating the resonant response.
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