Physicists at the University of Cologne have taken an important step forward in the pursuit of topological quantum computing by demonstrating the first-ever observation of Crossed Andreev Reflection (CAR) in topological insulator (TI) nanowires.

This finding, published under the title “Long-range crossed Andreev reflection in topological insulator nanowires proximitized by a superconductor” in Nature Physics, deepens our understanding of superconducting effects in these materials, which is essential for realizing robust quantum bits (qubits) based on Majorana zero-modes in the TI platform—a major goal of the Cluster of Excellence Matter and Light for Quantum Computing (ML4Q).

Quantum computing promises to revolutionize information processing, but current qubit technologies struggle with maintaining stability and error correction. One of the most promising approaches to overcoming these limitations is the use of topological superconductors, which can host special quantum states called Majorana zero-modes.