London, UK – August 26, 2025

A Major Step Towards Scalable Quantum Computing

Physicists have achieved a significant breakthrough in quantum computing by successfully creating high-fidelity entangling gates that connect remote superconducting quantum processors. This advancement, detailed in a new study, addresses a major hurdle in the field: the challenge of scaling quantum computers from small, isolated systems to large, powerful networks.

Superconducting quantum processors, a leading technology for building quantum computers, face a number of challenges when scaled up on a single chip. These include frequency crowding, wiring complexity, and packaging problems. The new research offers a solution by demonstrating that smaller processors can be linked together, creating a distributed network that is more manageable and scalable.

The breakthrough involves a method to directly entangle two quantum processors located 30 cm apart. This was achieved by using standing-wave modes in a connecting coaxial cable. The researchers were able to demonstrate high-fidelity entangling gates—a measure of accuracy—with a fidelity of 99.15% for a controlled-NOT gate and 98.03% for a controlled-Z gate. This level of accuracy is crucial for future fault-tolerant quantum computers, as even small errors can accumulate quickly.

Headlines of the Report

 * Remote Entanglement Achieved: Scientists have successfully created high-fidelity entangling gates between two superconducting quantum processors separated by a distance of 30 cm.

 * Overcoming Scalability Challenges: This method provides a viable strategy for building larger, more complex quantum systems by linking smaller, more manageable processors together.

 * High Fidelity is Key: The high accuracy of the entangling gates is a critical step towards building fault-tolerant quantum computers that can perform complex calculations with minimal errors.

 * Paving the Way for Networks: This achievement lays the groundwork for distributed quantum information processing, which is seen as a necessary step for the development of future large-scale quantum systems.

 * Efficient and Universal Protocol: The new protocol is faster and more efficient than previous methods, providing a robust solution for connecting quantum processors over a distance.

This development builds upon previous work in quantum state transfer and offers a more efficient protocol. Unlike feedback-based methods that take a longer time and have lower fidelity, this new approach is both fast and highly accurate. The ability to create these strong correlations between distant quantum bits, or qubits, is a critical step in building quantum networks that will one day be powerful enough to solve problems far beyond the reach of today’s supercomputers.