A group of researchers from Switzerland’s École Polytechnique Fédérale de Lausanne (EPFL) believes they have designed the thinnest metallic nanowire ever created. Remarkably, this wire remains stable even at 0 Kelvin.

The team, led by Chiara Cignarella with members Davide Campi and Nicola Marzari, devised an innovative approach to discover this nanowire. They aimed to leverage crystalline structures to identify suitable candidates without the need to build thousands in a lab.

The researchers focused on finding 3D crystals with the necessary structural and electronic properties that could be “exfoliated,” similar to how 2D materials like graphene are extracted from 3D crystals. This was the first attempt to exfoliate one-dimensional materials like carbon nanotubes.

They compiled a database of approximately 78,000 known 3D crystalline structures from various scientific sources worldwide, focusing on crystals held together by Van Der Waals forces. The team then developed a specialized algorithm to sift through the data, specifically seeking metallic wires, which are challenging to find due to their inherent instability.

The algorithm narrowed the list down to 800 candidates, which was further refined to 14. Four of these were selected for detailed study, including two metals and two semimetals. Among them was a notable chain composed of two carbon atoms and a copper atom, which exhibited stability and conductive properties even at normal temperatures due to resistance to Peierl distortions.

The team discovered that their 1D wire could be exfoliated from three distinct crystal sources: NaCuC2, KCuC2, and RbCuC2. These sources require minimal energy for extraction, and the resulting wire can be bent while retaining its metallic properties, making it suitable for flexible electronics.

Additionally, the researchers identified a semi-metal, Sb2Te2, which could aid physicists in studying excitonic insulators and potentially make quantum phenomena visible at macroscopic scales. According to the study authors, these findings are crucial for understanding how such materials could perform in real-world applications.

By Impact Lab