English

Laser technology reveals hidden gases in complex mixtures

1235
2024-01-11 14:29:04
See translation

Laser Network reported on January 11th that modern equipment has been fine tuned to detect highly specific gases, including trace gases found in the atmosphere, gases present in combustion exhaust emissions, and gases used in technology plasma applications.

They achieve this by calculating the percentage of light at a certain wavelength that is absorbed or attenuated by the sample. This way, the concentration of the gas can be calculated. The chemicals to be tested determine which detection wavelength should be used. In fact, multiple molecules can absorb the same amount of light, even at carefully selected wavelengths, which is a typical problem.

The efficiency of measurement methods is limited by this phenomenon called cross sensitivity. So far, this issue has been resolved, either by conducting additional measurements at various wavelengths, such as measuring spectra, or by using gas chromatography to separate interfering gases before measurement.

Dr. Ibrahim Sadiek, a former doctoral candidate at Gernot Friedrich and Leibniz Institute of Plasma Science and Technology, has now proven that there is a simpler solution.

Scientists have created a technology that enables them to surpass this cross sensitivity in absorption spectroscopy, even when producing single wavelength data. The scientific journal Science Report recently released a feasibility study on a novel, patent pending dual species one wavelength technology based on selective optical saturation.

This new technology utilizes the optical saturation phenomenon in molecules. Only very high light intensity - now easily generated by lasers - can lead to optical saturation. Subsequently, these molecules showed "transparency" in the absorption spectrum, indicating that the light emitted by radiation is no longer weakened.

The characteristic of the corresponding gas type is the point where the sample becomes transparent. Due to the deviation of concentration measurement caused by light saturation, it was previously believed to be harmful to absorption measurement and should be avoided at all costs.

As shown by Sadiek and Friedrich's research, using selective optical saturation can even measure the number of two molecules that completely interfere with each other at a given wavelength.

For example, a typical problem in practice is the detection of very low concentrations of chlorinated hydrocarbons in the atmosphere.

Currently, his team is conducting maritime research projects to advance the application of this technology in traditional absorption spectrometers. Then, on-site measurements will demonstrate the potential for reducing cross sensitivity to better explore the exchange process at the water air interface. If trace gases have sufficiently diverse saturation intensities, this method can theoretically be used to simultaneously detect multiple trace gases.

Source: Laser Net

Related Recommendations
  • 2D photoelectric neuron array can achieve broadband and low loss optical nonlinearity accessible to ambient light

    Light can calculate functions during propagation and interaction with structured materials, with fast speed and low energy consumption. The use of all optical neural networks for general computing requires an optical activation layer with nonlinear dependence on the input. However, existing optical nonlinear materials either have slow speeds or very weak nonlinearity at the level of natural light ...

    2024-03-20
    See translation
  • NASA will demonstrate laser communications on the space station to improve space communications capabilities

    Recently, in order to improve the National Aeronautics and Space Administration (NASA) space communications capabilities, NASA plans to send a technology demonstration called "Integrated LCRD Low Earth Orbit User Modem and Amplifier Terminal (ILLUMA-T)" to the space station in 2023.ILLUMA-T and the Laser Communications Relay Demonstration (LCRD), launched in December 2021, will together comp...

    2023-09-04
    See translation
  • QBeam launches innovative window ablation laser system to achieve free space optical communication

    QBeam is a leader in developing breakthrough optical products and announced today that its handheld laser ablation equipment is fully launched for free space optical communication in indoor office locations. The qBeam window ablation laser allows for the installation of optical communication terminals indoors by treating windows that otherwise block the infrared beams of the terminals.Commercial b...

    2024-02-15
    See translation
  • Real time measurement of femtosecond dynamics of relativistic intense laser driven ultra-hot electron beams

    In the interaction between ultra short and ultra strong laser and matter, electrons with short pulse width and high energy are generated, commonly referred to as "hot electrons". The generation and transport of hot electrons is one of the important fundamental issues in high-energy density physics of lasers. Superhot electrons can excite a wide range of ultrafast electromagnetic radiation, as well...

    2024-04-30
    See translation
  • Frankfurt Laser Company launches a new high-power fiber coupled laser diode

    The global leader in laser technology solutions, Frankfurt Laser, has launched a new series of high-power fiber coupled laser diodes, setting a new standard in the laser industry. The innovative 9XXnm high-power fiber coupled laser diode aims to optimize fiber laser pump source applications, providing unparalleled efficiency, compactness, and brightness.The New Era of Laser TechnologyThe latest pr...

    2024-05-13
    See translation