繁体中文

Scientists demonstrate powerful UV-visible infrared full-spectrum laser

517
2023-08-25 14:29:07
查看翻譯
Figure: a. Schematic diagram of the HCF-LN-CPPLN experimental setup. W. CaF? Window M, mirror.
b. The bright white light circular spots emitted by the CPPLN sample.
c. The first-order diffraction beam of B displays a colorful rainbow pattern from purple to red.
d. The HCF-LN-CPPLN module generates normalized spectra of the output full spectrum laser signal through the second NL HHG and third NL SPM effects.
Source: Lihong Hong, Liqiang Liu, Yuanyuan Liu, Junyu Qian, Renyu Feng, Wenkai Li, Yanyan Li, Yujie Peng, Yuxin Leng, Ruxin Li, and Zhi-Yuan Li

High brightness ultra-wideband ultra-continuous white light laser has attracted more and more attention in physics, chemistry, biology, material science and other scientific and technological fields. Over the past few decades, many different methods have been developed to produce supercontinuous white lasers.

Most of them utilize a variety of third-order nonlinear effects, such as self-phase modulation (SPM) occurring in microstructured photonic crystal fibers or homogeneous plates, or noble gas-filled hollow fibers. However, the quality of these supercontinuum light sources is subject to some limitations, such as the small pulse energy at the nanojoule level, and the requirements of complex dispersion engineering.

Another more efficient means of expanding the laser spectral range is through the various second-order nonlinear effects (2nd-NL) of the quasi-phase matching (QPM) scheme. However, the spectrum and power scaling performance of these pure 2N-NL schemes are still poor due to the narrow pump band width, limited QPM operating bandwidth, and reduced efficiency of high order harmonic energy conversion.

How to solve these bad limitations in the 2nd-NL and 3rd-NL systems and make both to produce full-spectrum supercontinuum lasers with spectral coverage from ultraviolet to mid-infrared has become a great challenge.

In a new paper published in Light: Science & Applications: A team led by Professor Zhi-Yuan Li and colleagues from the School of Physics and Optoelectronics at South China University of Technology in China has demonstrated an intense, quadruple-frequency UV-Vis-IR full-spectrum laser source (300 nm to 5000 nm, peak value -25 dB) with an energy of 0.54 mJ per pulse. Aerated hollow core fiber (HCF) from a cascade structure, exposed lithium niobate (LN) crystal plates, specially designed chirped periodically polarized lithium niobate crystals (CPPLN) pumped by a 3.9 mm, 3.3 mJ mid-infrared pump pulse.

Pumped by a 3.3mJ 3.9μm mid-infrared femtosecond pulse laser, the HCF-LN system can generate a strong mid-infrared laser pulse of double bandwidth as a secondary FW pump input to CPPLN, which supports efficient broadband HHG processing, further extending the spectral bandwidth to UV-Vis-IR. It is clear that this cascade structure creatively satisfies two prerequisites for the generation of full-spectrum white light: Condition 1, a strongly frequency-doubled pump femtosecond laser, and condition 2, a nonlinear crystal with an extremely high frequency up-conversion bandwidth. In addition, the system involves a large number of synergies between 2nd-NL and 3rd-NL effects.

The synergistic mechanism they have developed provides superior capabilities for constructing UV-Vis-IR global supercontinuum spectra and filling spectral gaps between various HHGS, far exceeding what has been achieved with single-acting 2N-NL or 3rd-NL effects previously employed.

As a result, this cascaded HFC-LN-CPPLN optical module enables previously unachievable levels of strong full-spectrum laser output, not only with great bandwidth (spanning four octave multiplicities), but also with a spectral profile of high flatness (from 300 to 5000 nm, flatness better than 25 dB) and large pulse energy (0.54 mJ per pulse).

"We believe that our proposal is to use the synergy of 2NL-HHG and 3rd-NL SPM effects to create an intense four-octave UV-vision-infrared full-spectrum femtosecond laser source, which is a big step toward building supercontinuous spectral white laser sources with greater bandwidth, energy, higher spectral brightness, and flatter spectral profiles." "This intense full-spectrum femtosecond laser will provide a revolutionary tool for spectroscopy and find potential applications in physics, chemistry, biology, materials science, information technology, industrial processing and environmental monitoring," the scientists said.

Source: Chinese Optical Journal Network
相關推薦
  • Toshiba has developed the world's highest precision 99.9% LiDAR technology

    Recently, Toshiba announced that in the field of LiDAR lidar for distance measurement, it has developed a technology that can track vehicles, people, and other objects with 99.9% accuracy, achieving the world's highest accuracy. And only using LiDAR to collect data can achieve 98.9% object recognition.In addition, the detection distance in rainstorm and dense fog environments has been increased by...

    2023-10-06
    查看翻譯
  • Leica Cine 1 laser TV with 4K display screen launched with a starting price of $8995

    Photography brand Leica has launched its first 4K movie and television. The Leica Cine 1 laser TV was announced a year later during the I FA 2022 period. This iconic photography brand is shifting some of its focus to projecting perfect images in our living room.featureThe Leica Cine 1 laser TV embodies Leica's philosophy in its camera design. Leica continues to provide precision optical engineerin...

    2023-10-19
    查看翻譯
  • Photonic hydrogel of high solid cellulose with reconfigurability

    Recently, Qing Guangyan, a researcher team from the Research Group on Bioseparation and Interface Molecular Mechanism (1824 Group) of Biotechnology Research Department of Dalian Institute of Chemical Physics, Chinese Academy of Sciences, designed and prepared a highly solid cellulose photonic hydrogel with reconfigurability and mechanical discoloration. This preparation method opens up a new way t...

    02-17
    查看翻譯
  • Telescope Discovers Record breaking Galaxy Space Laser

    A powerful telescope in South Africa has detected a space laser 5 billion light-years away from Earth, known as the "megamaser". Scientists named it Nkalakatha, which means "big boss" in Zulu language.Nkalakatha is the farthest hydroxyl giant detected so far, discovered by the MeerKAT telescope on the first night of the survey, which is expected to include 3000 hours of observation. The team of sc...

    2024-03-09
    查看翻譯
  • Free space nanoprinting beyond optical limitations can create 4D functional structures

    Two photon polymerization is a potential method for nanofabrication of integrated nanomaterials based on femtosecond laser technology. The challenges faced in the field of 3D nanoprinting include slow layer by layer printing speed and limited material selection due to laser material interactions.In a new report in Progress in Science, Chenqi Yi and a team of scientists in the fields of technical s...

    2023-10-09
    查看翻譯