Tiếng Việt

Scientists demonstrate powerful UV-visible infrared full-spectrum laser

328
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
  • Which automotive parts can use laser soldering technology

    Laser soldering is widely used in the manufacturing of automotive parts. Here are some common automotive parts that can be welded using laser soldering:Automotive electronic control systemEngine Control Unit (ECU): The engine control unit is the "brain" of the car engine, which receives signals from various sensors and controls the operation of the engine based on these signals. Laser soldering ca...

    02-10
    Xem bản dịch
  • The latest progress in laser chip manufacturing

    Modern computer chips can construct nanoscale structures. So far, only these tiny structures can be formed on top of silicon chips, but now a new technology can create nanoscale structures in a layer beneath the surface. The inventor of this method stated that it has broad application prospects in the fields of photonics and electronics, and one day, people can manufacture 3D structures on the ent...

    2024-07-29
    Xem bản dịch
  • Laser giant seeks $100 million financing for $422 million debt restructuring

    On August 6th local time, Luminar, a leading publicly traded company in the field of LiDAR, announced a $422 million debt restructuring and raised $100 million in new capital. This measure marks Luminar taking solid steps in optimizing its capital structure and enhancing its financial stability.In early May this year, this laser radar manufacturer released an open letter disclosing a major strateg...

    2024-08-09
    Xem bản dịch
  • Construction of Advanced New Laser Research Centers in American Universities

    The ATLAS R&D center is expected to be completed by mid-2026!A powerful new laser research facility located on the Foothills campus of Colorado State University will begin construction this month. The facility is planned to be put into use in mid-2026 and is the result of 40 years of laser development research at Colorado State University. It is a collaboration with the Fusion Energy Science P...

    2024-10-30
    Xem bản dịch
  • WVU engineers develop laser systems to protect space assets from the impact of Earth orbit debris

    The research from the University of West Virginia has been rewarded, as debris scattered in planetary orbits that pose a threat to spacecraft and satellites may be pushed away from potential collision paths by a coordinated space laser network.Hang Woon Lee, director of the Space Systems Operations Research Laboratory at the University of West Virginia, said that artificial debris dumps, including...

    2023-10-10
    Xem bản dịch