Fusion research company Tokamak Solutions has worked with partners at Oxford Instruments, the Czech Technical University and Institute of Plasma Physics, Prague to use high temperature superconducting magnets on a tokamak for the first time.
High temperature superconductors have remarkable properties: they conduct electricity with zero resistance, even with simple cooling by liquid nitrogen; they can withstand high magnetic fields and huge current densities - and we now know that they continue to be superconducting throughout the plasma pulse in a tokamak. It has long been known that high temperature superconductors could have an important role to play in the future of tokamak fusion research, but this is the first time they have actually been used for magnetic field coils on a tokamak.
In the experiment, two of the copper magnetic field coils on the Golem tokamak in Prague were replaced by high temperature superconductor in a simple cooling system known as a cryostat. Plasma pulses were then created in the normal way and the tokamak operated exactly as expected. A whole series of further experiments is now planned.
Dr Mikhail Gryaznevich, Chief Scientist of Tokamak Solutions, said "this was an important step for fusion research. We have learned a lot about the practical use of high temperature superconductors on tokamaks and these new materials are now certain to play a key role in the future of controlled fusion."
Dr Vojtìch Svoboda of the Czech Technical University in Prague said "although Golem is just a small tokamak, we are always looking for innovative ways to improve its performance and to progress fusion research. Last year Golem became the first tokamak to be operated fully remotely via the internet. This year, thanks to a stimulating collaboration with Tokamak Solutions and Oxford Instruments, it is the first tokamak to use high temperature superconductors."
Dr Radomír Panek of the Institute of Plasma Physics of the Academy of Sciences of the Czech Republic said "we are delighted to have supported this groundbreaking experiment. High temperature superconductors will be vital to the future of fusion research and this experiment has already provided useful data."
Jonathan Flint, Chief Executive of Oxford Instruments, said "Oxford Instruments has long established track record supplying tools and consultancy services to the fusion community and as the leading innovator in high performance magnets for scientific applications, so we were delighted to play our part in this successful collaboration."