Español

New Method - Observing how materials emit polarized light

59
2025-07-04 10:46:38
Ver traducción

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

Recomendaciones relacionadas
  • STREAMLIGHT Upgrade TLR RM Light with Red or Green Laser

    Streamlight, a leading supplier of high-performance lighting and weapon lights/laser aiming equipment, has launched upgraded models of its TLR RM 1 and TLR RM 2 series of lights, each now equipped with an HPL face cap, providing ultra bright beams of up to 1000 lumens and an extended range of up to 22000 candela.The popular TLR RM 1 and TLR RM 2 models are equipped with red or green lasers, both o...

    2024-02-23
    Ver traducción
  • Amplitude launches femtosecond lasers for industrial applications

    Recently, French femtosecond pulse and high peak power (PW class) laser manufacturer Amplitude announced that the company has launched a newly designed Satsuma X femtosecond laser, setting a new benchmark for industrial environments.This product was first announced in 2022 and is now available in a brand new design with proven durability and versatility. In pursuit of excellence and customer satis...

    2024-07-02
    Ver traducción
  • New progress in research on laser cleaning and improving the damage threshold of fused quartz components at Shanghai Optics and Machinery Institute

    Recently, the research team of the High Power Laser Element Technology and Engineering Department of the Shanghai Institute of Optics and Mechanics, Chinese Academy of Sciences, has made new progress in the study of improving the damage threshold of fused quartz elements through laser cleaning. The study proposes for the first time the use of microsecond pulse CO2 laser cleaning to enhance the dam...

    2024-07-08
    Ver traducción
  • More evidence of cosmic gravitational wave background: Laser interferometer gravitational wave observatory composed of two detectors

    The gravitational wave background was first detected in 2016. This was announced after the release of the first dataset by the European pulsar timing array. The second set of data has just been released, combined with the timed array of Indian pulsars, and both studies have confirmed the existence of the background. The latest theory seems to suggest that we are seeing a comprehensive signal of th...

    2024-05-21
    Ver traducción
  • Progress in the research and development of high-performance electrically pumped topology lasers in semiconductor manufacturing

    Topological laser (TL) is an ideal light source for future new optoelectronic integrated chips, designed and manufactured using topological optics principles to obtain robust single-mode lasers. Electrically pumped topology lasers have become a research hotspot due to their small size and ease of integration, but topology lasers based on electrical injection are still in the early stages of resear...

    2024-07-11
    Ver traducción