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arXiv · 2603.26473

Controlling isomer population using a dual-oscillator infrared free-electron laser

América Y. Torres-Boy·Anoushka Ghosh·Myles B. T. Osenton·Akash C. Behera·Sandy Gewinner·Marco De Pas·Heinz Junkes·Wieland Schöllkopf·Alexander Paarmann·Gert von Helden·Gerard Meijer
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Abstract

We report on the control and characterization of the isomer population of ions inside superfluid helium nanodroplets, using two-color operation of a dual-oscillator infrared free-electron laser. The timing of both lasers is highly synchronized, and their frequencies (or "colors") can be tuned independently over a wide range. Interaction of the singly deuterated proton-bound dimer of dihydrogen phosphate and formate inside helium nanodroplets with both colors enables the control over its isomer population and the recording of - one-color hidden - infrared spectra of individual isomers.

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América Y. Torres-Boy, Anoushka Ghosh, Myles B. T. Osenton, Akash C. Behera, Sandy Gewinner, Marco De Pas, Heinz Junkes, Wieland Schöllkopf, Alexander Paarmann, Gert von Helden, Gerard Meijer. 2026-03-27. Controlling isomer population using a dual-oscillator infrared free-electron laser. https://doi.org/10.1103/2hy7-w3qb

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