Thorlabs' Supercontinuum Generation Kits use femtoWHITE highly nonlinear fibers to spectrally broaden femtosecond pulses near 800 nm. The SCKB(/M) produces an output beam that combines the high power and spatial coherence of a laser with the broad spectrum of an incandescent source. The SCKB-CARS(/M) provides a stable beam with peaks at two separate center wavelengths.

When pumped with a femtosecond Ti:Sapphire Laser, the SCKB(/M) produces smooth, stable output providing even intensity across the 400 - 1600 nm spectral range, as shown in the plots on the Graphs Tab. The shape and intensity of the supercontinuum is determined by the pump wavelength, peak power, and pulse length. Information on possible lasers that are compatible with the SCKB is provided on the Kit Customization tab.

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Depending on the relative distance from the zero dispersion wavelength of the fiber, a variety of nonlinear effects are responsible for the creation of the spectrum; these effects include self-phase modulation, Raman scattering, soliton fission, and four-wave mixing. Please refer to J.M. Dudley, G. Genty, S. Coen. "Supercontinuum generation in photonic crystal fiber" Rev. Mod. Phys. 78, 1135 (2006) for a review of these effects in photonic crystal fibers.

The supercontinuum generation kits provide a set of of preselected and proven parts which allows the user to quickly set up the parts and start creating a supercontinuum spectrum. Due to this modular nature, the supercontinuum kits may be easily customized to a particular application by replacing components. For an example, please see the Kit Customization Tab above. The kits are shipped unassembled; however, pre-assembly is available for an additional fee. For details, please contact Technical Support.

Coherent Anti-Stokes Raman Scattering (CARS) Version
The SCKB-CARS(/M) contains a fiber with two zero-dispersion wavelengths for generation of an output with two distinct peaks, suitable for Coherent Anti-Stokes Raman Scattering applications. When pumped at a wavelength between the two zero-dispersion wavelengths, more than 99% of the light is converted into two spectral peaks.

The peak wavelengths are a result of the two zero-dispersion wavelengths that are determined solely by the design of the nonlinear PCF fiber. Due to this, the output wavelength is insensitive to changes in pump wavelength, pulse energy, pulse width, and spectral bandwidth. However, the relative intensity of the two peaks can be adjusted by varying of the pump wavelength.

For more information, please see K. M. Hilligsøe, T. V. Andersen, H. N. Paulsen, C. K. Nielsen, K. Mølmer, S. Keiding, R. E. Kristiansen, K. P. Hansen, and J. J. Larsen, "Supercontinuum generation a photonic crystal fiber with two zero dispersion wavelengths" Opt. Express 12, 1045 (2004).

Supercontinuum Generation Kit with femtoWHITE-800 Fiber Cell

Sample output spectra for the standard PCF module. Laser parameters are given in the tables below each plot.

Supercontinuum Generation Kit with femtoWHITE-CARS Fiber Cell

Sample output spectra for the CARS PCF module. Laser parameters are given in the tables below each plot.

Kit Customization Example

Due to its modular design using items compatible with Thorlabs's stock components, the Supercontinuum Generation Kit may be modified to fit the demands of a particular application. For example, the microscope objectives used in the kit may be easily replaced with appropriate aspheric lenses. This is particularly beneficial if pulse broadening is a concern; the single-element aspheric lenses will broaden the pulses less than the multi-element microscope objectives. With either objectives or aspheric lenses, the fiber coupling efficiencies will be in excess of 60%.

To replace the microscope objectives with aspheres, such as our C610TME-B, you will need Thorlabs' E09RMS RMS to M9 x 0.5 Adapter. Thread the M9 x 0.5-threaded lens into the adapter (an SPW301 spanner wrench is useful for this task), and then thread the adapter into the RMS-threaded holder on the 3-axis stage. A detail of the fiber coupling assembly with one objective replaced with an aspheric lens is shown in the photo to the upper right.

An additional example is shown to the lower right. In this case, the kit's standard fiber cell and mounts have been replaced with one of our nonlinear photonic crystal fibers and two of our fiber clamps (both HFF001 and HFF003 are shown, although in practice, one of the two designs could be used).

For more information on these and other customization options, please contact Technical Support.

OCTAVIUS-85M Femtosecond Laser

Lasers from Thorlabs and Strategic Partners

The supercontinuum generation kits may also be ordered as a complete package, including a femtosecond laser. Options include the Octavius femtosecond lasers manufactured by Thorlabs and fiber laser-based solutions from our strategic partner Menlo Systems. Laser specifications are given in the table below.

For more details or to receive a quote on a complete system with laser, pre-assembly services, or installation services, please contact Technical Support.

*With a 10 W Pump Laser.

The spectral output of the Supercontinuum Generation Kit can be tuned by changing the wavelength of the input light. The zero-dispersion wavelength (ZDW) of the kit’s fiber module is 750 nm, which allows Ti:Sapphire lasers to pump above and below the ZDW, accessing qualitatively different spectra.

The following spectra were taken using our Supercontinuum Generation Kit with a Coherent Chameleon Ultra II laser as the pump source. The results were collected by dispersing the light with a prism and then translating a slit and calibrated detector across the dispersed beam to measure the intensity across the spectrum. The data shows how the supercontinuum spectrum varies with input wavelength.

We thank Rupert Oulton and his group at Imperial College London for providing us with these results.

Plot Key

Input Laser Wavelength	Line Color*
700 nm
750 nm
800 nm
850 nm
900 nm

*Click on the line for an individual spectrum plot.