and Japan's Faraday 1867 Holdings signed a Letter of Intent (LOI) with the goal of scaling up the manufacture of high-temperature superconducting (HTS) tapes for widespread use in the large-scale deployment of fusion reactors, as well as to help drive the green energy transition. Coherent's excimer lasers in This collaboration promises wider applications.
In the last decade, the rapidly evolving prospect of carbon-free energy has led to advances in tokamak devices, while also driving increased demand for high-temperature superconducting magnetic tapes. High-temperature superconducting magnetic tapes, a key technology in the fabrication of ultra-strong electromagnets, have their primary application in magnetic confinement fusion reactors to confine and control plasma. Notably, Faraday Factory Japan LLC, a Japanese subsidiary of Faraday 1867 Holdings, has emerged as the world's leading manufacturer of high-temperature superconducting (HTS) magnetic tapes.
Coherent's LEAP excimer laser, an industry-standard pulsed laser deposition product, has given a major boost to the manufacturing process of high-temperature superconducting tapes.
Magnetic fields act to confine and control charged plasma in a tokamak device, according to Tokamak Energy, a British fusion startup. These strong magnetic fields allow the plasma to heat up to temperatures above 100 million degrees Celsius - the threshold needed for fusion to become a commercially viable energy source. After that, the powerful magnets in a spherical tokamak allow for more compact confinement, increasing plasma density and power while avoiding the expensive need for liquid helium cooling.
Powerful magnetic fields can be generated by passing high currents around an array of electromagnet coils that surround the plasma. The magnets are wound with what Tokamak Energy calls "breakthrough" high-temperature superconducting magnetic tape.
Faraday Factory Japan LLC, a subsidiary of Faraday 1867 Holdings, has been producing high-temperature superconducting tapes since 2012. The aforementioned letter of intent refers to the Japanese factory's strategy to meet the global demand for HTS tapes, and Coherent says that demand for such tapes is expected to grow tenfold between now and 2027.
The Japanese company uses ion beam-assisted deposition (IBAD), pulsed laser deposition (PLD), silver magnetron sputtering, and copper electrochemical plating, which require several manufacturing steps to make such tapes. Of these, excimer-based pulsed laser deposition (PLD) is the only proven mass-production method to create rare-earth barium copper oxide (REBCO) films with the qualities required for multilayer HTS tapes.
Pulsed laser deposition (PLD) is a potent tool for producing high-quality functional coatings," Faraday Plant describes on its website. The deposition process is generated by a plume of laser beams hitting a target on a metal strip with a buffer layer at high temperatures.HTS compounds are complex oxide materials, and the PLD method plays an important role in producing high-temperature superconducting layers with tightly controlled composition, thickness, and microstructure."
The letter of intent signed with Coherent is said to outline a strategy to increase high-temperature superconductor fabrication capabilities using the company's "LEAP" laser.
Coherent's LEAP excimer lasers are the industry standard for programmable logic devices for use in manufacturing HTS tapes," said Coherent. "The LEAP lasers are based on Argon Fluoride (ArF), Krypton Fluoride (KrF), and Xenon Chloride (XeCl) sources emitting at 193 nm, 248 nm, and 308 nm, respectively, and delivering output powers up to 300W. They are already in use in a range of industrial applications, such as laser lifters for the production of organic LED and MicroLED displays.
Kai Schmidt, Senior Vice President of Coherent's Excimer Laser Business Unit, said, "We know that countries involved in the fusion energy race are working hard to accelerate the supply chain of high-temperature superconducting tapes, growing by thousands of kilometers per year, in order to keep fusion technology moving forward at a rapid pace."
For his part, Sergey Lee, representative director of Faraday's Japan facility, added: "We have been working with Faraday 1867 for more than a decade, and our lasers are eager to play an important role in the ramp-up phase of HTS tape production. The application areas for HTS tapes are not limited to fusion reactors- -They include lossless energy transfer, zero-carbon aviation and container ships, helium-free NMR systems, advanced spacecraft propulsion systems, and more. These applications are driving double-digit annual growth in the HTS tape market, so the urgency of investing in HTS tape manufacturing capabilities is clear."
The HTS tape is one of the key technologies for realizing magnetic confinement fusion reactors like tokamaks. Tokamak designs are simpler, more compact, and cheaper to operate than previous technologies.HTS tapes can operate at temperatures in the tens of Kelvin range, eliminating the need for expensive cooling systems based on unsustainable liquid helium technology. Magnetic confinement fusion reactors are expected to ultimately be able to generate gigawatts of carbon-free electricity with a net gain of more than 10 percent and thus may play an important role in the global transition to green energy.
