Crystals Can Change the Properties of Laser Lightin Here is your first Forum Sat Sep 10, 2016 8:17 pm
by Eyes123456 • 29 Posts
Laser applications may benefit by the US National Institute of Standards and Technology (NIST) and China's Shandong University scientists study crystals. They found a potential way to circumvent the difficulties as a crystal laser technology a key part of the long-standing manufacturing. But their discovery also allow scientific experts behind thinking a lot.
Published today in the "scientific advances" magazine this study found that relatively large crystals used to change several burning laser pointer light which is important for the laser become useful tools is critical changes may be more likely to grow up, cheaper smaller rod-shaped crystallites stacked produced. So far, the research team out of the microcrystals in some characteristics superior to the conventional crystal, indicating that they can take advantage of this research is to achieve rapid economic development of large crystals explore a long-term signal to an end, without this method for fabricating large crystals will be extremely expensive.Microcrystalline but also challenges the traditional scientific theory and why they behave so characteristic.
You see the laser light color is often different from the way it was originally generated. Many laser infrared light to create, and then pass it through the energy of a crystal, whereby its wavelength is converted to visible color, such as green or blue. Typically, the kind of crystal is made of potassium pyrophosphate (KDP) phosphoric acid production, which is a common material, because of its features make it a very valuable: not only potassium pyrophosphate crystals can change the color of the light, it can also act as a switch , polarized light is changed (where the electric field in the direction of vibration) or to prevent it from before laser emission through the crystal. Polarized 2000mw green laser light through the fiber optic cable carrying data depends on the light, many applications rely on the timing of the laser pulse. Production of small potassium pyrophosphate crystals is easy, and those using a laser pointer in your pocket and telecommunications systems similar. But for higher energy scenarios, scientists for decades have been looking to make large-scale, high-quality crystal can survive repeated exposure to intense laser pulse, but it has been difficult to find a suitable solution.
The research team from the potassium pyrophosphate crystal growth was found useful results. These take the form of a crystal structure of hexagonal pole is a hollow tube and a few microns wide. Under the same conditions, the energy conversion efficiency of these separate potassium pyrophosphate microcrystals beyond even the best of potassium pyrophosphate crystals, which leads to the possibility of direct communication for crystal growth. The team also recommended crystal rods can be stacked like firewood as building a larger billions of tiny filaments. They all piled together before they can be coated with a thin layer of conductive material, heat conduction, so that they can handle high-intensity 200mw green laser light pulse repetition, which may expand its scope of application, if you can find an appropriate way of stacking .
Mystery is why the performance is so characteristic of microcrystalline. The basic laws of physics can not be explained. Regulation of physical models show that if used for energy conversion, these crystallites seems to break this rule, like crystals, optical media do not have symmetry around its center. Physicist at the National Institute of Standards and Technology Deng Lu said, "We contacted a large number of experts from various fields around the world, they can not explain this phenomenon, there is no theory can explain the initial growth mechanism of this peculiar crystals. from our current understanding of view, this will be a challenge to learn crystalline condensed matter physics research. "Although the Red Laser Pointer theory is to catch the experimental data, Deng said that their team is focused on growing rods can be stacked microcrystalline engineering challenges.
"Every ten minutes we can achieve growth of more than 1,000 micro-organization on a single sheet of glass, so the growth of large area is not a problem," he said. "We need to figure out how to grow a large cross-section having a nearly uniform structure, since the final assembly it is important."