English

Progress in Laser Physics: Reducing Residual Amplitude Modulation for Accurate Measurement

1281
2024-03-18 13:56:19
See translation

Driven by the pioneering work of scientists such as John Young Hall, significant progress has been made in precision measurement in the field of laser physics. His contribution to laser frequency stability and precise measurement using lasers has led to groundbreaking techniques that significantly reduce residual amplitude modulation.

John Hall's research focuses on understanding and manipulating stable lasers, laying the technical foundation for measuring small fractional distance changes caused by gravitational waves passing through them. This work on laser arrays earned him the 2005 Nobel Prize in Physics.

On this basis, JILA and NIST academicians Jun Ye and their team embarked on an ambitious journey to expand the boundaries of precision measurement. They focus on improving the Pound Reverse Hall (PDH) method, a specialized technique developed by RV Pound, Ronald Drever, and Jan Hall, which plays a crucial role in precision optical interferometry and laser frequency stability.

Although the PDH method is crucial for ensuring laser frequency stability, the limitations of residual amplitude modulation (RAM) may affect measurement accuracy. In a recent paper published in Optica, Ye's team, along with JILA electronics staff Ivan Ryger and Hall, proposed a new PDH method. This method reduces RAM to an unprecedented low level, simplifies the system, and enhances robustness.

PDH technology is the foundation of various experiments, from gravitational wave interferometers to optical clocks. Further improvement of this technology can bring progress to many scientific fields.

The PDH method was introduced in 1983 and has become the cornerstone of laser physics, widely used in various experiments. It precisely measures laser frequency or phase fluctuations by introducing special "sidebands" around the main beam (referred to as the "carrier"). Comparing these sidebands with the main carrier helps detect subtle changes in frequency or phase relative to the reference, thereby reducing noise and errors.

Physicists use this technique to detect different environments, such as optical cavities made of mirrors, by "locking" the laser into the cavity. However, noise like RAM can alter the relative offset of the reference beam, thereby affecting stability.

Reducing RAM is crucial for improving the stability of PDH technology and laser measurement. The new method developed by JILA researchers is expected to simplify this task and make significant progress in precision measurement and laser physics.

Source: Laser Net

Related Recommendations
  • Tiny yet Powerful: How Lasers on Chips Change the Game Rules of Photonics

    Chip level ultrafast mode-locked laser based on nanophotonic lithium niobate.Researchers have created a compact mode-locked laser integrated into a nanophotonic platform, capable of generating high-power and ultrafast optical pulses. The breakthrough in miniaturization of MLL technology can significantly expand the application of photonics.Innovation in mode-locked laser technologyTo improve the t...

    2023-12-27
    See translation
  • Coherent launches EDGE CUT20 OEM cutting solution

    Coherent launches EDGE CUT20 OEM cutting solution. By deeply integrating the new CUT20 laser cutting head with EDGE FL20 fiber laser, this solution brings three core advantages to high-performance sheet metal cutting: ultimate precision cutting quality, unprecedented process control capability, and intelligent process insights. At the heart of the EDGE CUT20 package is a co-engineered laser-and-...

    11-11
    See translation
  • Aerotech will start laser laboratory in Fürth, Germany

    Aerotech announced the opening of a new laser laboratory in F ü rth, Germany. The laboratory operates in collaboration with existing service providers, aiming to provide European customers with a physical platform capable of testing complex laser process solutions to enhance local support. Aerotech has been developing high-precision motion control systems for applications in laser material proce...

    11-24
    See translation
  • Acousto optic modulation of gigawatt level laser pulses in the ambient air of Nature Photonics

    An interdisciplinary research group, including the German synchrotron radiation accelerator DESY and the Helmholtz Institute in Jena, Germany, reported that invisible gratings made of air not only are not damaged by lasers, but also maintain the original quality of the beam. The relevant research has been published in Nature Photonics under the title of "Acousto opt modulation of gigawatt scale la...

    2023-10-12
    See translation
  • Nanjing University of Science and Technology has made new progress in the field of programmable lensless holographic cameras

    Recently, Professor Chen Qian and Professor Zuo Chao's research group from the School of Electronic Engineering and Optoelectronic Technology at Nanjing University of Science and Technology proposed a minimalist optical imaging method based on programmable masks - programmable Fresnel zone aperture lensless imaging technology. The related achievement, titled "Lensless Imaging with a Programmable F...

    04-14
    See translation