Broadband stimulated Raman scattering spectroscopy by a photonic time stretcher.
Stimulated Raman scattering spectroscopy is a powerful technique for label-free molecular identification, but its broadband implementation is technically challenging. We introduce and experimentally demonstrate a novel approach based on photonic time stretch. The broadband femtosecond Stokes pulse, after interacting with the sample, is stretched by a telecom fiber to ≈15ns, mapping its spectrum in time. The signal is sampled through a fast analog-to-digital converter, providing single-shot spectra at 80-kHz rate. We demonstrate ≈10-5sensitivity over ≈500cm-1in the C-H region. Our results pave the way to high-speed broadband vibrational imaging for materials science and biophotonics.
Francesco
F
Saltarelli
Vikas
V
Kumar
Daniele
D
Viola
Francesco
F
Crisafi
Fabrizio
F
Preda
Giulio
G
Cerullo
Dario
D
Polli