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arXiv · 1206.6060

Overlapping Resonances Interference-induced Transparency: The $S_0 \to S_2/S_1$ Photoexcitation Spectrum of Pyrazine

Timur Grinev·Moshe Shapiro·Paul Brumer
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Abstract

The phenomenon of "overlapping resonances interference-induced transparency" (ORIT) is introduced and studied in detail for the $S_0 \to S_2/S_1$ photoexcitation of cold pyrazine (C$_4$H$_4$N$_2$). In ORIT a molecule becomes transparent at specific wavelengths due to interferences between envelopes of spectral lines displaying overlapping resonances. An example is the $S_2\leftrightarrow S_1$ internal conversion in pyrazine where destructive interference between overlapping resonances causes the $S_0 \to S_2/S_1$ light absorption to disappear at certain wavelengths. ORIT may be of practical importance in multi-component mixtures where it would allow for the selective excitation of some molecules in preference to others. Interference induced cross section enhancement is also shown.

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Timur Grinev, Moshe Shapiro, Paul Brumer. 2012-09-17. Overlapping Resonances Interference-induced Transparency: The $S_0 \to S_2/S_1$ Photoexcitation Spectrum of Pyrazine. https://doi.org/10.1063/1.4748515

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