Tiếng Việt

Scientists demonstrate powerful UV-visible infrared full-spectrum laser

521
2023-08-25 14:29:07
Xem bản dịch
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
Đề xuất liên quan
  • Osram's new laser headlights "Yutianba" are unveiled

    Recently, OSRAM, a well-known global automotive lighting brand, announced the launch of its modified new laser headlights - the Yutianba laser headlights. Laser headlights were once regarded by many car companies as the "successor" of LED headlights, and German century old automotive lighting expert Osram is precisely the pioneer of laser light sources for automotive headlights. Since the 2014 BMW...

    2024-05-06
    Xem bản dịch
  • Shanghai Optical Machinery Institute has made progress for the first time in hard X-ray zoom beam imaging

    Recently, the High Power Laser Physics Joint Laboratory of Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, completed the research of hard X-ray zoom beam splitting imaging on the micro focus X-ray source for the first time, and solved the problem of beam splitter limitation in the hard X-ray band. The related achievements are titled "Bifocal photo scene imaging in the...

    2024-04-08
    Xem bản dịch
  • It is said that laser additive manufacturing is good, but what is the advantage?

    When it comes to additive manufacturing, some people may not have heard of it, but when it comes to its other name: 3D printing, no one is unaware.In fact, the name 'additive manufacturing' better illustrates the essence of this processing method. From ancient times to the present, humans have put in great effort to achieve the goal of processing 'raw materials into the shapes we need'. From the S...

    2023-11-08
    Xem bản dịch
  • CO2 laser cutting machine for battery shell shaped parts: an innovative tool in energy technology manufacturing

    The development of new energy technology has made battery technology the engine for advancing clean energy. In battery manufacturing, the cutting of battery shell shaped parts is a crucial step. CO2 laser cutting machines have become an innovative tool for promoting the development of this field due to their high efficiency and precision. This article will delve into the important characteristics ...

    2023-12-25
    Xem bản dịch
  • IoTech shapes the flexible future of 3D printed electronic products

    The rapidly developing IoTech enterprise headquartered in Israel will showcase at LOPEC 2024 how its disruptive digital manufacturing continuous laser assisted deposition technology shapes the future of microelectronics and additive manufacturing.Herv é Javice, co-founder and CEO of ioTech, commented, "We are delighted to be attending the LOPEC exhibition for the first time and showcasing ...

    2024-02-27
    Xem bản dịch