Two Dimensional Superconductivity in NbSe2

Scientists are investigating the potential of  Two Dimensional materials, which are composed of a single layer or a few ultrathin layers of atoms and have unique physical, electrical and optical properties. This study was published in Nature Physics. They used the niobium diselenide in the study.

Researchers at the University of Minnesota and Cornell University recently carried out a study investigating the Superconductivity of few-layer niobium diselenide, a layered transition metal that shows a unique intrinsic Ising-type spin-orbit coupling. The study shows that the state of a few-layer NbSe2 has a two-fold symmetry, which differs greatly from the structure of its crystals.

Vlad S. Pribiag, one of the researchers who carried out the study said that there is enormous interest in two-Dimensional materials, such as, niobium diselenide because when they are prepared to be only a few atomic layers thick, they often have new properties, that are not present in thick samples of the same material. NbSe2 is a Superconductivity in its bulk form, but when small layer samples are prepared, the crystal symmetry changes, making the much more resilient to applied magnetic fields.In the past, researchers found that could be a topological superconductor. Topological  are a unique class of with non-trivial topological properties. These unique Superconductivity have attracted crucial attention, as they prevent quantum bits from losing the data they store. They could enable the creation of new quantum computers that are topologically protected.

Researchers found the Superconductivity state of a few layers NbSe2 has a two-fold symmetry, which is strikingly distinct from the three-fold symmetry of the crystal. This two-fold symmetry is consistent with the presence of two competing states that are very close in energy which could be related to topological Superconductivity and we are now working on follow-up experiments that aim to determine this.

In their experiments, Pribiag and his colleagues found that anisotropy appeared as they rotated a magnetic field on their sample’s plane. The researchers investigated this observation further using two different types of samples. One sample they measured the critical field The second type of sample, studied by the team at Cornell University, had a thin insulating layer between the and a magnetic material, which allowed them to tunnel into the NbSe2 The two sets of measurements they collected both showed a two-fold anisotropy.