Nederlands

New Method - Observing how materials emit polarized light

61
2025-07-04 10:46:38
Bekijk vertaling

Many materials emit light in ways that encode information in its polarization. According to researchers at École Polytechnique Fédérale de Lausanne (EPFL), Switzerland, polarization is key for future technologies, from quantum computers to secure communication and holographic displays.
Among such phenomena is a form known as circularly polarized luminescence (CPL), a special type of light emission produced by chiral materials, in which light waves spiral either left or right as they travel.

 



Standard CPL techniques are often slow, narrowly focused, or unable to pick up faint signals, says EPFL, especially when studying advanced materials with fleeting or subtle polarization effects. These limitations have slowed the quest to fully understand how chiral materials interact with light.

Now, a team led by Professor Sascha Feldmann at EPFL’s Laboratory for Energy Materials has developed a high-sensitivity, broadband, time-resolved spectroscopy technique that captures the complete set of polarization states (the so-called "Stokes vector"). The work, including shared blueprints, is described in Nature.

Wide window

The new technique does this across a wide spectral window (400–900 nm), and at time intervals ranging from just nanoseconds up to several milliseconds, all with a noise floor as low as one ten-thousandth the intensity of the polarized light being emitted by a material. The new technique also captures linear and circular polarization signals at the same time, which helps identify and correct for polarization artifacts that often disrupt other methods.

The EPFL team says it designed the instrument “with straightforward, off-the-shelf components, making it widely adoptable.” They are sharing the full optical schematics and a compendium of “non-obvious” error sources to open the field up for others.
They used an electronically-gated camera and polarization optics to record the full Stokes vector in real time, tracking changes in light emission from different types of molecules that feature both strong and weak polarized luminescence. By recording the complete polarization fingerprint, the new set up can uncover details that other approaches miss, says EPFL.

 



The new approach successfully captured polarization changes in materials that had never been tracked in such detail before. It reproduced benchmark results for well-studied molecules, and it revealed previously unseen dynamics in organic emitters and complex systems where light emission happens on both fast and slow timescales.

With its combination of high sensitivity, wide spectral coverage, and nanosecond time resolution, the technique is said to open an unprecedented window onto the realm of excited-state polarization dynamics and symmetry-breaking. The team has also made their blueprints and automation algorithms public in an effort to democratize the field and help speed up discoveries worldwide.

Source: optics.org

Gerelateerde aanbevelingen
  • University of California, Los Angeles Joins the American High Power Laser Facility Alliance

    The University of California, Los Angeles is joining LaserNetUS, a high-power laser facility alliance established by the Department of Energy, aimed at advancing laser plasma science.Unique facilities are located in universities and national laboratories across the United States and Canada, providing a wide range of opportunities for researchers and students.The Phoenix Laser Laboratory at the Uni...

    2023-09-15
    Bekijk vertaling
  • Super-resolution fluorescence microscopy utilizes fluorescent probes and specific excitation and emission programs

    Super-resolution fluorescence microscopy surpasses the diffraction limit of what used to be a barrier by using fluorescent probes and specific excitation and emission programs. Most SR technologies heavily rely on image computation and processing to retrieve SR information. However, factors such as fluorescence group photophysics, chemical environment of the sample, and optical settings may cause ...

    2024-01-23
    Bekijk vertaling
  • Application and Effect of Laser Cleaning

    Mold cleaning: Mold plays a very important role in industrial production. Currently, there are over a thousand mold related enterprises in China, driving the related output value to nearly 10 billion yuan. Among them, mold cleaning is an essential step in mold production. Laser can achieve contactless cleaning of molds, which is very safe for the surface of the mold, ensuring its accuracy, and can...

    2023-10-14
    Bekijk vertaling
  • Bodor Laser has been approved by Shandong Engineering Research Center

    Recently, the Development and Reform Commission of Shandong Province announced the list of Shandong Engineering Research Centers for 2024. bodor Laser has been recognized as the "Advanced Laser High end Intelligent Manufacturing and Application Shandong Engineering Research Center" and is the only enterprise in the laser intelligent manufacturing industry to be listed.As an important component of ...

    2024-07-17
    Bekijk vertaling
  • Breakthrough in Silicon Based Room Temperature Continuous Wave Topological Dirac Vortex Microcavity Laser

    With the explosive growth of data traffic, the market is extremely eager for hybrid photonic integrated circuits that can combine various optical components on a single chip.Silicon is an excellent material for photonic integrated circuits (PICs), but achieving high-performance laser sources in silicon still poses challenges. The monolithic integration of III-V quantum dot (QD) lasers on silicon i...

    2023-10-26
    Bekijk vertaling