The University of Southampton
University of Southampton Institutional Repository

Comparison of SC fibers for fs Ti:Sapphire based hyperspectral CARS microscopy

Comparison of SC fibers for fs Ti:Sapphire based hyperspectral CARS microscopy
Comparison of SC fibers for fs Ti:Sapphire based hyperspectral CARS microscopy

Hyperspectral coherent anti-Stokes Raman scattering (CARS) microscopy is a rapidly developing field enabling label-free, chemically selective bio-imaging based on Raman signatures [1]. A significant factor limiting its clinical application is the complexity of current laser sources. A solution immediately relevant to two-photon excited fluorescence imaging laboratories is coherently broadening a fs Ti :Sapphire laser seed in a fiber to provide the Raman wavelengths via spectral-focusing (SF) CARS. The NKT fiber with two Zero Dispersion Wavelengths (ZDWs) is one option but the spectrum exhibits low Power Spectral Density (PSD) because of the large (>800 nm) spectral broadening. Here we perform the first systematic comparison sweeping (i) input pump power, (ii) pump wavelength and (iii) fiber length comparing the coherent SC from a femtoWHITE-CARS (2 ZDWs) fiber, a fiber with one ZDW offset above the seed wavelength, and an all-normal dispersion (ANDi) fiber. Starting with the seed laser polarisation aligned to a principal fiber axis, we show the total experimentally measured spectral output and importantly the polarisation resolved spectral component on the orthogonal axis, which is a measure of the nonlinear power-dependent depolarisation[2]. This orthogonal component will degrade the efficiency of the CARS signal but still contributes to the bio-toxicity that limits the maximum power for imaging. Finally, we show representative SF-CARS microscopy images to showcase the power of this technique.

IEEE
Herdzik, K. P.
c94de69f-61c5-4ba0-bed5-dd13c5d9ec0b
Bourdakos, K. N.
83f6fc3a-db12-476b-9a78-4aad8756f82f
Richardson, D. J.
ebfe1ff9-d0c2-4e52-b7ae-c1b13bccdef3
Horak, Peter
520489b5-ccc7-4d29-bb30-c1e36436ea03
Price, J. H.V.
fddcce17-291b-4d01-bd38-8fb0453abdc8
Mahajan, S.
3e8fb3d0-f384-4182-ac26-b3063056a3c6
Herdzik, K. P.
c94de69f-61c5-4ba0-bed5-dd13c5d9ec0b
Bourdakos, K. N.
83f6fc3a-db12-476b-9a78-4aad8756f82f
Richardson, D. J.
ebfe1ff9-d0c2-4e52-b7ae-c1b13bccdef3
Horak, Peter
520489b5-ccc7-4d29-bb30-c1e36436ea03
Price, J. H.V.
fddcce17-291b-4d01-bd38-8fb0453abdc8
Mahajan, S.
3e8fb3d0-f384-4182-ac26-b3063056a3c6

Herdzik, K. P., Bourdakos, K. N., Richardson, D. J., Horak, Peter, Price, J. H.V. and Mahajan, S. (2019) Comparison of SC fibers for fs Ti:Sapphire based hyperspectral CARS microscopy. In 2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference, CLEO/Europe-EQEC 2019. IEEE.. (doi:10.1109/CLEOE-EQEC.2019.8873199).

Record type: Conference or Workshop Item (Paper)

Abstract

Hyperspectral coherent anti-Stokes Raman scattering (CARS) microscopy is a rapidly developing field enabling label-free, chemically selective bio-imaging based on Raman signatures [1]. A significant factor limiting its clinical application is the complexity of current laser sources. A solution immediately relevant to two-photon excited fluorescence imaging laboratories is coherently broadening a fs Ti :Sapphire laser seed in a fiber to provide the Raman wavelengths via spectral-focusing (SF) CARS. The NKT fiber with two Zero Dispersion Wavelengths (ZDWs) is one option but the spectrum exhibits low Power Spectral Density (PSD) because of the large (>800 nm) spectral broadening. Here we perform the first systematic comparison sweeping (i) input pump power, (ii) pump wavelength and (iii) fiber length comparing the coherent SC from a femtoWHITE-CARS (2 ZDWs) fiber, a fiber with one ZDW offset above the seed wavelength, and an all-normal dispersion (ANDi) fiber. Starting with the seed laser polarisation aligned to a principal fiber axis, we show the total experimentally measured spectral output and importantly the polarisation resolved spectral component on the orthogonal axis, which is a measure of the nonlinear power-dependent depolarisation[2]. This orthogonal component will degrade the efficiency of the CARS signal but still contributes to the bio-toxicity that limits the maximum power for imaging. Finally, we show representative SF-CARS microscopy images to showcase the power of this technique.

This record has no associated files available for download.

More information

Published date: 1 June 2019
Venue - Dates: 2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference, CLEO/Europe-EQEC 2019, ICM – International Congress Centre, Munich, Germany, 2019-06-23 - 2019-06-27

Identifiers

Local EPrints ID: 436331
URI: http://eprints.soton.ac.uk/id/eprint/436331
PURE UUID: 1c711ad4-fbab-4a77-90d7-4fabac2d366b
ORCID for K. N. Bourdakos: ORCID iD orcid.org/0000-0003-2737-5657
ORCID for D. J. Richardson: ORCID iD orcid.org/0000-0002-7751-1058
ORCID for Peter Horak: ORCID iD orcid.org/0000-0002-8710-8764
ORCID for J. H.V. Price: ORCID iD orcid.org/0000-0003-0256-9172

Catalogue record

Date deposited: 06 Dec 2019 17:30
Last modified: 18 Mar 2024 03:32

Export record

Altmetrics

Contributors

Author: K. P. Herdzik
Author: K. N. Bourdakos ORCID iD
Author: Peter Horak ORCID iD
Author: J. H.V. Price ORCID iD
Author: S. Mahajan

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×