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Attosecond stable dispersion-free delay line for easy ultrafast metrology.

ABSTRACT: We demonstrate a dispersion-free wavefront splitting attosecond resolved interferometric delay line for easy ultrafast metrology of broadband femtosecond pulses. Using a pair of knife-edge prisms, we symmetrically split and later recombine the two wavefronts with a few tens of attosecond resolution and stability and employ a single-pixel analysis of interference fringes with good contrast using a phone camera without any iris or nonlinear detector. Our all-reflective delay line is theoretically analyzed and experimentally validated by measuring 1st and 2nd order autocorrelations and the SHG-FROG trace of a NIR femtosecond pulse. Our setup is compact, offers attosecond stability with flexibility for independent beam-shaping of the two arms. Furthermore, we suggest that our compact and in-line setup can be employed for attosecond resolved pump-probe experiments of matter with few-cycle pulses.

SUBMITTER: Tyagi A

PROVIDER: S-EPMC9122952 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Attosecond stable dispersion-free delay line for easy ultrafast metrology.

Tyagi Akansha A Sidhu Mehra S MS Mandal Ankur A Kapoor Sanjay S Dahiya Sunil S Rost Jan M JM Pfeifer Thomas T Singh Kamal P KP

Scientific reports 20220520 1

We demonstrate a dispersion-free wavefront splitting attosecond resolved interferometric delay line for easy ultrafast metrology of broadband femtosecond pulses. Using a pair of knife-edge prisms, we symmetrically split and later recombine the two wavefronts with a few tens of attosecond resolution and stability and employ a single-pixel analysis of interference fringes with good contrast using a phone camera without any iris or nonlinear detector. Our all-reflective delay line is theoretically ...[more]

PMID: 35595769

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