Nanotechnology Applications of a Tunable Supercontinuum Laser Light Source

Different types of tunable laser source (TLS) are available on the market to suit a wide variety of applications. However, it is important to choose the right technology for specific applications, as each technology comes with certain limitations. The range of parameters which have to be taken into account can be quite confusing.

This article outlines a range of real applications where the versatile TLS from Photon etc. can be used effectively.

The TLS employs a filtering device to select a wavelength from a super-continuum source, also called a white laser. These pulsed light sources have become a common tool in a variety of applications, from fluorescence lifetime experiments to flow cytometry. However, in most cases, only a part of the light emitted is required. As a result, tunable filters are often utilized.

The Laser Line Tunable Filter (LLTF) developed by Photon etc. is a tunable bandpass filter built on volume holographic gratings. These resonant glass gratings are positioned in a specific configuration to select a part of the super-continuum output without compromising its polarization.

In contrast to other filters that are commercially available in the marketplace, the LLTF is capable of 70db of isolation, a unique specification for applications with high demands on sensitivity. It also provides a wide tunable range, from 1000 to 2300nm, and from 400 to 1000nm within a single filter, with bandwidths of 4nm and 2.5nm respectively.

Moreover, the filtered beam has exceptional pointing stability that enables easy recoupling to both mono- and multi-mode fibers.

Applications of the Tunable Laser Source

Detecting Breast Cancer Cells Using Gold Nanoparticles

Gold plasmonic nanoparticles (AuNPs) have interesting properties for a wide range of biological applications, and are widely used as biomarkers. However, these particles are very small, and the complex surroundings in which they move make it difficult to observe and characterize them.

In order to overcome this problem, Patskovsky et al.¹ utilized a hyperspectral dark field microscope in backscattering configuration, and also used a TLS instead of the standard white light illumination.

With this arrangement, the researchers were able to sweep the illumination across the range from 400 to 1000nm. The high output power and the broad range of wavelengths of the source proved to be important parameters in this empirical study.

The researchers were easily able to track the spatial distribution and position along the z-axis of the AuNPs targeting a cell surface receptor, CD44. This receptor is actively expressed in cancer stem cells. The hyperspectral imaging arrangement can prove useful in biological applications, where a combination of spectral and spatial data is required.

Single-Walled Carbon Nanotube Thermopile

In addition to biological applications, Photon etc’s TLS is used in the characterization of carbon nanomaterials. This technology was used by St-Antoine et al.² to determine the spectral response of the photovoltage of a single-walled carbon nanotubes thermopile.

The TLS was also utilized to acquire basic absorption spectra, and made it possible to analyze the wavelength dependency of the device, especially in the near infrared and visible ranges, from 500 to 1800nm.

High power combined with small bandwidth makes the TLS suitable for optimum characterization of single-walled nanotubes. Moreover, the technology enables high efficiency fiber coupling to illuminate specimens within a restricted vacuum chamber.

Benefits of Photon etc's Tunable Laser Source

Photon etc’s TLS makes it possible to select a fast and wide wavelength from the robust and stable Fianium super-continuum sources.

New advances in super-continuum white laser technology now make it possible to create the full VIS-NIR wavelength range from a single source. The wide spectral range shifts from UV to NIR with a bandwidth down to 0.4nm. In addition, a large tuning range makes it possible to select highly precise wavelengths.

This makes the TLS an excellent tool for advanced research applications in nanotechnology.

Conclusion

The tunable laser source from Photon etc. serves as an excellent tool in various nanotechnology applications, across fields such as life science, materials science, and electronics.

It is used to observe and characterize gold plasmonic nanoparticles, which are used as biomarkers to detect breast cancer cells. The technology also helps in determining the spectral response of the photovoltage of a single-walled carbon nanotubes thermopile. Thus, the TLS serves as a versatile calibration tool for sophisticated characterization of various materials.

References

[1] Sergiy Patskovsky, Eric Bergeron, David Rioux, and Michel Meunier, Hyperspectral darkfield microscopy of PEGylated gold nanoparticles targeting CD44-expressing cancer cells, Biophotonics, 2013.

[2] Benoit C. St-Antoine, David Ménard, and Richard Martel, Single-Walled Carbon Nanotube Thermopile For Broadband Light Detection, Nano Letters, vol 11, 609-613, 2011.

About Photon etc.

Photon etc. offers state-of- the-art photonic and optical research instrumentation, from laser line tunable filters to widefield and microscopy hyperspectral imaging systems. Its patented spectral imaging and optical sensing technologies provide solutions for a wide variety of scientific and industrial applications. From material analysis to medical imaging, Photon etc.’s expertise and spirit of innovation allow the exploration of uncharted territories.

Photon etc. aims to provide each researcher, engineer and technician with access to the latest innovations in optical and photonic instrumentation. As pioneers in Bragg-based hyperspectral imaging, Photon etc. offers state-of-the-art instruments, driven by its clients’ desires to surpass limitations in measurement and analysis.

Inspired by the scientific creativity found in Montreal and Quebec, Photon etc. promotes open and collaborative innovation and excellence. The dynamic team of this company is proud to offer to its clients innovative and reliable instruments, based on the latest scientific advances in photonics and optics. At Photon etc., the primary wish is to develop a long term relationship with the clients by providing products adapted to their specific needs, combined with personalized service and support.

This information has been sourced, reviewed and adapted from an article by Marc Verhaegen and Laura-Isabelle Dion-Bertrand from Photon etc.

For more information on this source, please visit Photon etc.