Coherent lasers will help expand the scale of fusion tokamaks

Coherent company's excimer lasers can be more widely used in fusion reactor applications, after the US based photonics giant signed a "letter of intent" with Japan's Faraday 1867 Holdings.

Faraday 1867, headquartered in Kanagawa Prefecture, is said to have become the world's leading manufacturer of high-temperature superconducting (HTS) tape through its subsidiary Faraday Japan factory.

This tape is used for strong electromagnets to limit plasma in magnetic confinement fusion reactors.

According to the British fusion startup Tokamak Energy, a magnetic field is used in Tokamak to limit and control the charged plasma that constitutes the "fuel" of fusion reactors.

These strong fields allow the plasma to be heated to temperatures above 100 million degrees Celsius - the threshold required for fusion to become a commercially viable energy source - the powerful magnets in a spherical tokamak can achieve more compact confinement, increase plasma density and power, while eliminating the need for expensive cooling using liquid helium.

A magnetic field is generated by transmitting a large current around an array of electromagnetic coils surrounding the plasma, which are wound around what Tokamak Energy calls "groundbreaking" HTS tapes.

Functional coatings
The Faraday factory has been producing high-temperature superconducting tape since 2012, and the company stated that the demand for tape is expected to increase tenfold from now to 2027.

Manufacturing tape requires several manufacturing steps, and this Japanese company uses ion beam assisted deposition (IBAD), pulse laser deposition (PLD), silver magnetron sputtering, and copper electrochemical plating.

PLD is an extremely powerful tool for growing high-quality functional coatings, "Faraday Factory said on its website. The deposition process occurs when a laser beam hits a target on a metal strip with a buffer layer at high temperature, resulting in a plume.
HTS compounds are a complex oxide material; the PLD method plays an important role in producing HTS layers with strictly controlled composition, thickness, and microstructure.

It is said that the letter of intent signed between the company and related companies outlines the strategy of using the company's "LEAP" laser to improve HTS manufacturing capacity.

Coherent company LEAP excimer laser is an industry standard for PLD and can manufacture HTS tape, "Coherent company stated. The LEAP laser is based on argon fluoride (ArF), krypton fluoride (KrF), and xenon chloride (XeCl) light sources with emission wavelengths of 193 nm, 248 nm, and 308 nm, with an output power of up to 300 W.

They have been used in a series of industrial applications, such as the laser lift off stage for the production of organic LED and microLED displays.

Senior Vice President, Excimer Laser Business Unit, Coherent Company
Kai Schmidt commented, "We know that countries participating in the nuclear fusion energy competition are seeking a sustainable supply chain of high-temperature superconducting tape that spans thousands of kilometers per year to maintain the fast track of fusion technology development.

We have been a partner with Faraday 1867 for over a decade, and we are eager to provide lasers to support the production ramp up phase of HTS tape.

Sergey Lee, the representative director of the Faraday Japan factory, added, "The application of HTS tape goes beyond fusion reactors: they include non-destructive energy transfer, zero carbon aviation and container ships, helium free MRI systems, advanced propulsion of spacecraft, and more.

Overall, these applications are driving the double-digit annual growth rate of the HTS tape market, which increases the urgency of investing in HTS tape manufacturing capabilities.

In further cooperation with Japanese companies, the relevant companies have reached an agreement to obtain $500 million each from electronic giants Mitsubishi Electric and Electric Equipment in exchange for a share of their silicon carbide (SiC) wafer business.
This $1 billion transaction will result in two Japanese companies each holding 12.5% of a new subsidiary, while the related companies retain 75% of the controlling stake.

This development was initiated after a strategic review of the SiC business earlier this year. Although it will not directly affect the photonics related businesses of the relevant companies, it should enable the parent company to focus almost entirely on its laser, optical, and photonics work.

With the shift towards fully electric vehicles and power transmission, the demand for SiC based broadband gap power electronic devices is expected to grow exponentially, and related companies have long been the main suppliers of basic SiC materials for manufacturing individual semiconductor devices.

Source: Laser Network