US achieves superconductor breakthrough, creates new material for quantum leap

“A topological superconductor uses a delocalized state of an electron or hole (a hole behaves like an electron with positive charge) to carry quantum information and process data in a robust manner,” explained the researchers in a press release.

It is essential for the development of robust quantum computers, which exhibit a significant sensitivity to various forms of interference.

“Our material could be a promising candidate for developing more scalable and reliable quantum computing components,” said Peng Wei, an associate professor of physics and astronomy, who led the team.

An innovative combination

The researchers combined trigonal tellurium, a material known for its chiral and non-magnetic properties, with a surface state superconductor generated on a thin film of gold. 

This innovative combination resulted in a two-dimensional interface superconductor with distinctive characteristics that set it apart from conventional superconductors.

“By creating a very clean interface between the chiral material and gold, we developed a two-dimensional interface superconductor,” emphasized Wei.

Trigonal tellurium’s chirality, its inability to be superimposed on its mirror image, introduces a unique element to the superconductor. Furthermore, the interface between the chiral material and gold establishes a favorable environment.

“The interface superconductor is unique as it lives in an environment where the energy of the spin is six times more enhanced than those in conventional superconductors,” Wei explained.

This amplification creates the potential to utilize excitations at the interface to generate spin quantum bits, or qubits. For context, these are the fundamental units of quantum information in quantum computers.

Applications in quantum computing

The implications of this discovery reach into the rapidly evolving field of quantum computing, which utilizes the principles of quantum mechanics to address complex problems beyond the capabilities of classical computers.

The researchers successfully constructed high-quality, low-loss microwave resonators. These are essential components of quantum computers, using materials significantly thinner than those commonly used in the industry.

“We achieved this using materials that are one order of magnitude thinner than those typically used in the quantum computing industry. The low-loss microwave resonators are critical components of quantum computing and could lead to low-loss superconducting qubits,” Wei remarked while highlighting the significance of this accomplishment.

He further underscored the primary difficulty in quantum computing, which lies in mitigating decoherence, or the degradation of quantum information within a qubit system.

Decoherence, the phenomenon where a quantum system loses its fragile quantum information as a result of interactions with its surroundings, constitutes a significant obstacle in the development of practical quantum computers.

The researchers’ innovative methodology, utilizing non-magnetic materials to establish a cleaner interface, may facilitate the creation of more scalable and dependable components for quantum computing.

Further discoveries

The team’s work extended beyond the initial discovery. They observed that the interface superconductor undergoes an intriguing transition under the influence of a magnetic field. This suggests a transformation into a “triplet superconductor.”

This type of superconductor demonstrates increased stability in the presence of magnetic fields. Additionally, they demonstrated that the superconductor naturally suppresses sources of decoherence arising from material defects, which is a prevalent challenge in the field.

The emergence of this new superconductor material, coupled with its potential to tackle key challenges in quantum computing and its promising applications, signals a new era in this transformative field.

This brings us closer to the realization of quantum computers capable of handling problems of unprecedented complexity.