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Title: Background-penalty-free waveguide enhancement of CARS signal in air-filled anti-resonance hollow-core fiber
We study coherent anti-Stokes Raman spectroscopy in air-filled anti-resonance hollow-core photonic crystal fiber, otherwise known as “revolver” fiber. We compare the vibrational coherent anti-Stokes Raman signal of N 2 , at ∼2331 cm −1 , generated in ambient air (no fiber present), with the one generated in a 2.96 cm of a revolver fiber. We show a ∼170 times enhancement for the signal produced in the fiber, due to an increased interaction path. Remarkably, the N 2 signal obtained in the revolver fiber shows near-zero non-resonant background, due to near-zero overlap between the laser field and the fiber cladding. Through our study, we find that the revolver fiber properties make it an ideal candidate for the coherent Raman spectroscopy signal enhancement.  more » « less
Award ID(s):
2013771
NSF-PAR ID:
10441061
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Optics Letters
Volume:
47
Issue:
17
ISSN:
0146-9592
Page Range / eLocation ID:
4339
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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