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arXiv · 1807.07857

Visible-spanning flat supercontinuum for astronomical applications

Aakash Ravi·Matthias Beck·David F. Phillips·Albrecht Bartels·Dimitar Sasselov·Andrew Szentgyorgyi·Ronald L. Walsworth
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Abstract

We demonstrate a broad, flat, visible supercontinuum spectrum that is generated by a dispersion-engineered tapered photonic crystal fiber pumped by a 1 GHz repetition rate turn-key Ti:sapphire laser outputting $\sim$ 30 fs pulses at 800 nm. At a pulse energy of 100 pJ, we obtain an output spectrum that is flat to within 3 dB over the range 490-690 nm with a blue tail extending below 450 nm. The mode-locked laser combined with the photonic crystal fiber forms a simple visible frequency comb system that is extremely well-suited to the precise calibration of astrophysical spectrographs, among other applications.

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Aakash Ravi, Matthias Beck, David F. Phillips, Albrecht Bartels, Dimitar Sasselov, Andrew Szentgyorgyi, Ronald L. Walsworth. 2018-10-10. Visible-spanning flat supercontinuum for astronomical applications. https://doi.org/10.1109/jlt.2018.2872423

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