Improved spectrometer based on nonlinear optics

November 12, 2008

Scientists at Stanford University and Japan's National Institute of Informatics have created a new highly sensitive infrared spectrometer. The device converts light from the infrared part of the spectrum to the visible part, where the availability of superior optical detectors results in strongly improved sensing capabilities.

The research will appear in the Nov. 24 issue of Optics Express, the Optical Society's open access journal. The new spectrometer is 100 times more sensitive than current commercial optical spectrum analyzers used in industrial applications such as optical communication, semiconductor microelectronics and forensic analysis.

Current spectrometers being used on the market today cover a wide spectral range, allow for moderately fast wavelength sweeps, have a good spectral resolution and don't require cryogenic cooling. However, the sensitivity of these instruments is limited, making them unsuitable for capturing single-photon-level spectra at telecommunication wavelengths.

Cryogenic cooling can increase the sensitivity of these devices, yet reduces the usefulness for industrial applications. One possible solution is to up-convert near-infrared to visible light in a nonlinear medium. The up-converted photons can then be detected using a single-photon detector for visible light.

The authors use a single-photon counting module, which results in 100 times better sensitivity. They implemented the frequency conversion via sum-frequency generation in a periodically poled lithium niobate waveguide, which can be thought of as combining two low-energy photons to get one high-energy photon.

Key Findings

-- The up-conversion based spectrometer's sensitivity is 100 times higher compared to current commercial optical spectrum analyzers.

-- Cryogenic cooling is not required for increased sensitivity, making the device practical for a variety of industrial applications.

-- The cost and system complexity of the spectrometer is reduced because it only uses one single-photon detector instead of an array of detectors.

Citation: "Waveguide-Based Single-Pixel Up-Conversion Infrared Spectrometer," Optics Express, Vol. 16, Issue 24.

Source: Optical Society of America

Explore further: New technology could mean better chemical analysis on earth and in space

Related Stories

How we plan to bring dark matter to light

September 17, 2015

Long before we had the atomic theory of matter, scientists knew the air was real, even though it was invisible. This was because we could see its action as the wind caressed the leaves in trees.

The road to ultrahigh-resolution X-ray spectrometers

November 29, 2011

Two recent developments at the Advanced Photon Source explore paths to routine use of sub-meV x-rays to probe low-energy excitations in matter. The first is a remarkable experimental demonstration of an x-ray optical scheme ...

Developing miniaturized spectrometer-on-a-chip

August 3, 2012

( -- The Composite Infrared Spectrometer (CIRS) is big. It's powerful and it discovered, among other things, that Saturn's mysterious moon Enceladus was one of the very few worlds in the solar system that radiated ...

Recommended for you

Test racetrack dipole magnet produces record 16 tesla field

November 30, 2015

A new world record has been broken by the CERN magnet group when their racetrack test magnet produced a 16.2 tesla (16.2T) peak field – nearly twice that produced by the current LHC dipoles and the highest ever for a dipole ...

Turbulence in bacterial cultures

November 30, 2015

Turbulent flows surround us, from complex cloud formations to rapidly flowing rivers. Populations of motile bacteria in liquid media can also exhibit patterns of collective motion that resemble turbulent flows, provided the ...

'Material universe' yields surprising new particle

November 25, 2015

An international team of researchers has predicted the existence of a new type of particle called the type-II Weyl fermion in metallic materials. When subjected to a magnetic field, the materials containing the particle act ...

CERN collides heavy nuclei at new record high energy

November 25, 2015

The world's most powerful accelerator, the 27 km long Large Hadron Collider (LHC) operating at CERN in Geneva established collisions between lead nuclei, this morning, at the highest energies ever. The LHC has been colliding ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.