self-cleaning optical fiber can help in monitoring environment and diagnosing cancer
Utilizing two glasses with a different refractive index and stacked with a specific arrangement has allowed researchers to develop for the first time a multimodal fiber with a parabolic refractive index with transmission up to the mid-infrared and high nonlinearity. The spectrum of short pulses of light injected into the fiber massively broadens to span from the visible to mid-infrared. Significantly, unlike in conventional multimode fibers, the light beam remains smooth as the result of self-cleaning dynamics induced by the parabolic refractive index. Such a light source with ultrabroad spectrum, smooth beam and high power finds applications in e.g. environmental sensing or high-resolution imaging for medical diagnostics. Credit: Tampere University

Researchers at Tampere University have successfully developed a novel optical fiber design allowing the generation of rainbow laser light in the molecular fingerprint electromagnetic region. This new optical fiber with a self-cleaned beam can help in developing applications for, for example, pollutant tagging, cancer diagnostics, environmental monitoring, and food control. The finding was published in the journal Nature Communications.

When a high-powered ultrashort pulse of light interacts with a material such as a glass optical fiber, a range of highly nonlinear interactions take place that cause complex changes in both the temporal and spectral properties of the injected light. When taken to the extreme, such interactions can lead to the generation of a rainbow laser of light commonly referred to as a supercontinuum light source. Since its first demonstration in a special type of optical fiber in 2000, supercontinuum laser light has revolutionized many areas of science, ranging from metrology and imaging at unprecedented resolution to ultrabroadband remote sensing and even the detection of exoplanets.

The current bottleneck with current supercontinuum sources, however, is that they are based on optical fibers that support a single transverse intensity profile or mode, which inherently limits their optical power. What’s more, conventional optical fibers are made of silica glass with transmission limited to the visible and near-infrared region of the spectrum. Extension of supercontinuum light to other wavelength regimes such as the mid-infrared requires optical fibers made of so-called soft glasses, but these possess a lower damage threshold than silica, limiting even more the power of the supercontinuum beam.

Non-silica optical fiber with a self-cleaned beam

Recently, a different type of optical fiber with a refractive index that varies continuously across the fiber structure has been shown to yield a dramatic increase in supercontinuum power, while still preserving a smooth beam intensity profile. “The refractive index variation of such graded-index optical fibers leads to periodic focusing and defocusing of the light inside the fiber that enables coupling between spatial and temporal nonlinear light-matter interactions. This leads to a self-cleaning mechanism that yields supercontinuum light with high power and a clean beam profile. As well as their many applications, they also provide a means of studying fundamental physics effects such as wave turbulence”, says Professor Goëry Genty, the leader of the research group at Tampere University.

While these fibers have recently attracted significant attention from the research community, their use has been, up to now, restricted to the visible and near-infrared. In collaboration with the group of Profs. Buczynski and Klimczak at the University of Warsaw (Poland) and the group of Prof. Dudley in the University of Burgundy France-Comté (France), the Tampere team demonstrated for the first time the generation of a two-octave supercontinuum from the visible to mid-infrared in a non-silica graded-index fiber with a self-cleaned beam.

“This problem has now been solved by using a particular design that utilizes two types of lead-bismuth-gallate glass rods with different refractive indices drawn to yield a nanostructured core. The result is a graded-index fiber with an effective parabolic refractive index profile with transmission up to the mid-infrared, and, as cherry on the cake, enhanced nonlinear light-matter interactions,” says researcher Zahra Eslami.

Great potential in diagnostics and monitoring

The mid-infrared is of crucial interest as it contains the characteristic vibrational transitions of many important molecules.

“The novel solution will lead to more efficient supercontinuum light sources in the mid-infrared with many potential applications e.g., for pollutant tagging, cancer diagnostics, machine vision, environmental monitoring, quality and food control,” explains Genty.

The researchers anticipate that this novel type of fiber will very soon become an important and standard material for the generation of broadband sources and frequency combs. More information: Zahra Eslami et al, Two octave supercontinuum generation in a non-silica graded-index multimode fiber, Nature Communications (2022). DOI: 10.1038/s41467-022-29776-6 Journal information: Nature Communications

Provided by Tampere University Citation: Self-cleaning optical fiber can help in monitoring environment and diagnosing cancer (2022, April 26) retrieved 26 April 2022 from This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.


What to watch on HBO Max: New shows and movies in July 2022

Few streaming services are able to compete with the star power of HBO Max. 2022 will be a change of pace for the streamer though, as day-and-date blockbuster releases are now over. Of course, there is still plenty to watch on HBO Max, including new releases like Pretty Little ...

View more: What to watch on HBO Max: New shows and movies in July 2022

Eye Movements Could Be the Missing Link in Our Understanding of Memory

Summary: Visual scanpaths during memory retrieval tasks were associated with the quality of the memory. Researchers say the replay of a sequence of eye movements helps boost memory reconstruction. Source: The Conversation Humans have a fascinating ability to recreate events in the mind’s eye, in exquisite detail. Over 50 years ...

View more: Eye Movements Could Be the Missing Link in Our Understanding of Memory

Smart Implants to Monitor Healing

Summary: A newly developed, self-powered smart implant is able to monitor spinal fusion healing. Source: University of Pittsburgh Spinal fusion—fusing two vertebrae together—can treat a wide variety of spinal disorders. Often, surgeons will use a cage to provide support where the disk once was between the vertebrae. But what if ...

View more: Smart Implants to Monitor Healing

The Mathematics of Human Behavior: New Model Can Spot Liars and Counter Disinformation

Summary: A new mathematical model has the potential to accurately distinguish a misunderstanding from false information and lies. Source: The Conversation Understanding the human mind and behavior lies at the core of the discipline of psychology. But to characterize how people’s behavior changes over time, I believe psychology alone is ...

View more: The Mathematics of Human Behavior: New Model Can Spot Liars and Counter Disinformation

AcBel Polytech aims to provide aggregated energy services

Power supply maker AcBel Polytech aims to become a provider of aggregated energy services through integrating power of different generation types, according to company chairman Jerry Hsu. For the purpose, AcBel will develop a smart energy management system for collecting information on power consumption and undertaking big data analysis ...

View more: AcBel Polytech aims to provide aggregated energy services

Taiwan science parks record revenues of over NT$1,317 billion for January-April

Government-developed Hsinchu Science Park (HSP), Southern Taiwan Science Park (STSP) and Central Taiwan Science Park (CTSP) generated combined revenues of NT$1,317.224 billion (US$45.03 billion) in January-April 2022, growing 19.53% on year, according to Ministry of Science and Technology (MOST). HSP recorded 4-month revenues of NT$534.367 billion, rising 12.59% on ...

View more: Taiwan science parks record revenues of over NT$1,317 billion for January-April

Voice economy (1): Voice as a vehicle of comfort

Most people look at the evolution of society from a B2C perspective, expecting to get the most positive responses. But this can be a trap for business. Because of my career, I naturally start from a B2B perspective, exploring my views that are different from others, or capturing the best ...

View more: Voice economy (1): Voice as a vehicle of comfort

Chipmakers focus on heat dissipation in manufacturing process upgrades

High heat dissipation and other thermal management technologies are increasingly required for both front- and back-end chipmaking processes by companies engaged in the automotive, HPC, industrial and network chip segments, according to industry sources. Materials demand for manufacturing processes with enhanced heat dissipation performance has been growing robustly, said the ...

View more: Chipmakers focus on heat dissipation in manufacturing process upgrades

TSMC completes cleanroom construction at R&D center in Japan

Apple M2 chip: Everything you need to know

Apple Mixed Reality Headset: M2 Chip and 16GB RAM, For 2022?

Marvel already confirmed Doctor Doom in the MCU, but we almost missed it

NASA Introduces 2022 Class of Flight Directors – Meet the 7 New Additions to the Team

Industry minister to visit Czech Republic, Poland for nuclear energy sales

States race to woo Foxconn as EV, Chip fab plan take shape

Payments Council seeks government help post RBI’s fintech order

TCS eyes non-metro offices to move closer to tech talent

Influencers cry foul over delayed pay at Trell; 100 more staff leave firm amid troubles

Reliance, PremjiInvest, CP Group, Swiggy look to bid for Metro India unit

COVID-19 Positive Patients at Far Higher Risk of Developing Serious Neurodegenerative Disorders


Top Car News Car News