We have a winner!
The inventors have picked Atmospheric monitoring of greenhouse gas isotopes for determining and attributing emission sources by Kat Potter
as their winner for this competition. Here's what they had to say:
"All the entries where great, and thanks for all the contributions and the time dedicated. All finalist grasped the technology well and clearly laid out the application with a focus on the technologies key features. This made it especially difficult to decide on the winner. However we decided on Kat Potter’s entry as she thought outside the box with the application in isotope analysis. Kat carried out great due diligence and detailed both technical application notes and commercial due diligence. We were particularly impressed as Kat pointed out the competitors in the market, their limitations and how best to take our technology forward. Thanks to all who contributed to this competition, the research, time and effort carried out by everyone has truly helped us in understanding applications better and where the technologies’ potential lies. This will no doubt help us take the laser bloodhound forward and put it into the real world! Finally congratulation to Kat Potter for an excellent submission and well thought out proposal!"
Hello Marblarverse! We’re excited to present to you a novel laser spectroscopy technique co-developed by the Science and Technology Facilities Council and Princeton. A spectrometer is a device that determines the chemical composition of samples. In regular infrared spectroscopy, which we all know and love, a laser beam is absorbed by the chemical bonds in a sample, causing them to vibrate. The resulting spectrum of absorption at a specific wavelength can be used to quantify the presence of a given molecule.
Now, instead of measuring how much of our infra-red laser is absorbed by the sample, we looked at another way the light is affected: dispersion
. This is what we measure in CLaDS (Chirped Laser Dispersion Spectroscopy). Go check out the slides
for some more detail on how it all works. In addition to being some seriously cool science, measuring dispersion instead of absorption gives the method some huge advantages over the standard absorption principle. Advantages include enhanced sensitivity
(up to parts per billion/trillion (ppb/ppt) - putting any natural blood-hound to shame!) and signal-to-noise
ratio as well as high immunity to intensity variations
(making it useful in situation where environmental conditions scatter the beam, e.g. in open path detection
). Most interestingly we have a dynamic range from ppb to almost 100% concentration - useful in for example exhaust analysis, where analyte concentrations range from trace amounts to near-opacity (see slides).
CLaDS is currently designed for single, light molecule (e.g. CO2, N2O, etc.) species detection
. Simultaneous multiple species and larger gas molecules can be detected; however this requires a broadband source that will increase the system’s size, complexity and cost.
Keeping in mind the limitations of the technique, there are a lot of areas in trace-gas sensing where the device could be valuable:
- breath diagnostics, e.g. using ammonia as a biomarker for liver disease,
- process and air-quality monitoring, such as exhaust gas analysis, which requires high dynamic range,
- atmospheric measurements using open path detection, where laser power received by the detector varies due to e.g. rain and dust in the air.
The technology is at its early stages and specific applications have not been explored thoroughly, so we’re keen to hear any specific ideas within the above categories - as well as completely new ideas of course. A great entry would:
- create a competitive advantage from the device’s unique features (high sensitivity/dynamic range, immunity to laser power variations) while not requiring detection of many/complex species.
- be as specific as possible,
- outline a clear market potential and path to market as well as comparing CLaDS to existing competitiors in the space.
- High sensitivity in the parts per billion (ppb) to parts per trillion (ppt) range and comparable to gas chromatography. If lower sensitivity measurements in parts per million (ppm) are required, a cheaper laser-type can be used in the form of a tunable diode lasers rather than a quantum cascade (QC) laser.
- Linear response over the full dynamic range (ppb to 100%). Traditional devices have limited dynamic range e.g. 3-300 ppm for CO2 for the absorption-based QC-laser system described here. This is due to the non-linearity associated with the physics of absorption.
- Highly immune to laser power variations, thus deployable in situations where received power may fluctuate due to environmental conditions that scatter the beam (such as outdoor atmospheric measurements subject to rainfall, snow, fog, dust, soot, etc.) or mechanical vibration.
- The above makes it especially suitable for remote open path detection to accurately analyse the chemical composition of the atmosphere - more info in the slides.
- Robust and compact (shoebox size).
- Limitation: the device is specific to only a single species, depending on the frequency of the laser. By adding multiple lasers or using a broadband laser device, several compounds can be analyzed in parallel, however, this adds additional cost and complexity to the system.
I’m Damien Weidman and my lab is based in Oxford, England. I've developed CLaDS together with Gerard Wysocki in one of the Space technology labs run by the Science & Technology Facilities Council. My focus is primarily on the development of ultra-sensitive tuneable-laser-based optical sensors and methods for atmospheric, environmental, medical, and security applications – currently a pretty hot R&D area.
CLaDS was actually discovered by pure serendipity when we noticed some odd effects in the data while we were playing around with different laser setups. As it turns out, the technique ended up having several unique features that could make it have a big impact on the challenges faced in e.g. the environmental, security and health sectors. I’m sure we haven’t even scratched the surface of what we can do with this cool gadget, so we’re very excited to hear your input.
Patent WO/2011/058330: Detecting species in a dilute medium
Optics Express, Vol. 18, Issue 25, pp. 26123-26140 (2010): Molecular dispersion spectroscopy for chemical sensing using chirped mid-infrared quantum cascade laser