Provided by Osaka University
The research group of Professor Masakatsu Murakami at the Institute of Laser Engineering Osaka University successfully verified for the first time the generation and development of a megatesla-class ultra-high magnetic field, which is comparable with the magnetic field strength of a neutron star, over a period using a new method--"microtube implosion"--with 3D simulations. The 3D simulation was performed using the supercomputer "OCTOPUS" of the Osaka University Cybermedia Center.
This result was found by Professor Murakami in October 2020 by irradiating a micron-sized hollow cylinder with a powerful ultrashort pulse laser.[1, 2] This confirms a new physical mechanism that generates an extremely high magnetic field in the megatesla range, which is 1000 times stronger than the magnetic field strength (kilotesla) that can be generated on the ground at present. According to Professor Murakami, "The strongest magnetic field generated and observed on the ground is at the kilotesla level, which is equivalent to 10 million times the earth's magnetic field, and no method has been proposed that can surpass this value over the past half-century."
The group irradiated a powerful laser from the outside of a hollow cylinder with a diameter of approximately 1/10 that of a hair and found that a megatesla-class ultra-high magnetic field 1000 times stronger than the kilotesla level along the axial direction is generated. This is the principle of microtube implosion.
Provided by Osaka University
By creating a relatively weak magnetic field along the cylindrical axis in advance, these high-speed electrons moving in the material at a speed close to the speed of light form a ring-shaped spin current structure with a small radius of several microns. This current reaches 10-18 A/m2, and as a result, a megatesla-class magnetic field, which is said to be observed near black holes, can be achieved in the laboratory. If this megatesla class magnetic field can be demonstrated, its impact on basic science, e.g., quantum theory effects and undeveloped areas of cosmic physics, which have not even been discussed so far, would be immeasurable. Professor Murakami said, "In the future, based on the physics concept of megatesla magnetic field generation, we would like to work on the conceptual design of an ultra-compact particle accelerator that can replace a huge accelerator and a compact fusion method that can be defined as a hybrid of inertial confinement fusion and magnetic confinement fusion."
Reference:
[1] "Generation of megatesla magnetic fields by intense-laser-driven microtube implosions"
Scientific Reports 10, 16653 (2020).
https://doi.org/10.1038/s41598-020-73581-4
[2] YouTube Murakami'slab: https://www.youtube.com/watch?v=eL4w1uGRk4U
This article has been translated by JST with permission from The Science News Ltd.(https://sci-news.co.jp/). Unauthorized reproduction of the article and photographs is prohibited.