UTe2 Unleashes New Superconductivity Secrets
UTe2, an unconventional superconductor studied by international researchers, exhibits unique superconductivity under high magnetic fields, offering new technological potential.
Tracking Unconventional Superconductivity
UTe2 is a high-flyer among superconducting materials that conducts electricity without loss in a different way than conventional superconductors. To understand this phenomenon, it is important to look at superconductivity closely. Superconductivity occurs when electrons in a material move without resistance, enabled by the formation of Cooper pairs.
In unconventional superconductivity, such as spin-triplet superconductivity, Cooper pairs are formed through mechanisms that are not yet fully understood. It is believed that these superconductors make use of magnetic fluctuations. Heavy-fermion superconductors, which are materials in which conduction electrons come together collectively, could also be related to unconventional superconductivity. UTe2 is considered both a spin-triplet and a heavy-fermion superconductor.
The researchers have found that UTe2 exhibits extremely high stability against magnetic fields. With a transition temperature of 1.6 kelvin, it can withstand a critical magnetic-field strength of 73 tesla. This sets a record for the ratio between transition temperature and critical magnetic-field strength in superconductors.
Special Treatment for a Demanding Material
Although UTe2 is not suitable for technical applications due to its low transition temperature and radioactivity, it is ideal for exploring the physics behind spin-triplet superconductivity. The researchers used samples of UTe2 with thicknesses of a few micrometers for their experiments. These samples were prepared using a high-precision ion beam and were sealed in epoxide glue due to the material's air-sensitivity.
To definitively prove that UTe2 is a spin-triplet superconductor, spectroscopy studies need to be conducted under strong magnetic fields. However, current spectroscopy methods struggle at magnetic fields above 40 tesla. The researchers are working on developing novel techniques to provide conclusive evidence.
The exceptional stability of UTe2 against magnetic fields opens up possibilities for future applications. Materials that can withstand high magnetic fields and conduct electricity without loss are crucial for the development of superconducting magnets used in technologies like magnetic resonance imaging (MRI) scanners.
