A new era in quantum computing begins with the advancement in the development of Logical Qubits thanks to the collaboration between Microsoft and Quantinuum.

Microsoft and Quantinuum have made significant advances in the field of quantum computing through their joint project, Azure Quantum. Both companies claimed to have developed a new generation of highly reliable logical qubits, essential for the practical implementation of quantum computing. A few months ago, they introduced this type of qubit by applying Microsoft’s qubit virtualization system to Quantinuum's H series trapped ion qubits.

In an initial phase, they successfully generated four logical qubits from 30 physical qubits, with a logical error rate that improved 800 times compared to the physical error rate. Although Microsoft considered this result impressive, they continued to explore new frontiers, and their efforts paid off. The collaboration has now progressed to produce 12 logical qubits from 56 physical qubits in Quantinuum's H2 machine, demonstrating a remarkable fidelity of 99.8% in two-qubit operations.

The team demonstrated the entanglement of these logical qubits within a complex configuration known as the Greenberger-Horne-Zeilinger (GHZ) state, which is more sophisticated than previous Bell state preparations. This entanglement resulted in a circuit error rate of 0.0011, significantly lower than the 0.024 error rate of the physical qubits. These advancements not only highlight the potential for deeper quantum computations but also pave the way for fault-tolerant quantum computing, an essential step to fully leverage the capabilities of quantum technology.

The collaboration between Microsoft and Quantinuum also represents a milestone in applying quantum computing to solve real-world problems, especially in the field of chemistry. By integrating logical qubits with artificial intelligence (AI) and high-performance computing (HPC), they successfully tackled a complex scientific problem related to estimating the ground state energy of an important catalytic intermediate.

The process began with identifying the active site of the catalyst through HPC simulations. Then, logical qubits were used to simulate the quantum behavior of this active site. The results from these simulations were used to train an AI model that ultimately provided an accurate estimate of the ground state energy. This comprehensive workflow represents the first instance where quantum computing, HPC, and AI have come together to solve a scientific problem, demonstrating the practical utility of quantum technologies.

While the current results do not yet represent a total scientific quantum advantage—defined as the ability of quantum computers to solve problems beyond the reach of classical computers—they do evidence the potential of quantum systems to outperform classical methods in certain situations. The hybrid approach used in this study illustrates how quantum computing can enhance the accuracy of chemical calculations, particularly for complex problems that are challenging to resolve with classical systems.

The successful demonstration of this hybrid workflow not only underscores the capabilities of logical qubits but also emphasizes the importance of integrating quantum computing with other advanced technologies. By combining the strengths of quantum computing, AI, and HPC, researchers can develop innovative solutions to urgent scientific challenges.

The Azure Quantum platform serves as a hub where quantum computing, AI, and HPC converge. This ecosystem is designed to facilitate seamless interaction between different hardware architectures, enabling researchers to harness the strengths of each technology. By combining quantum capabilities with AI, researchers can use machine learning algorithms to analyze large datasets and extract valuable insights, significantly accelerating the research and development process.

Looking ahead, Microsoft has expressed its commitment to advancing its Azure Quantum platform to support a variety of qubit architectures, including neutral atom and topological qubits. The integration of these diverse technologies aims to improve the reliability and scalability of quantum computing, with the ultimate goal of developing systems that address some of the world's most significant challenges.

Rajeeb Hazra, CEO of Quantinuum, remarked that "the ability of our systems to triple the number of logical qubits while we have less than doubled the amount of physical qubits, from 30 to 56, is a testament to the high fidelity and full connectivity of our H series trapped ion hardware." He stated that their current H2-1 hardware, combined with Microsoft’s qubit virtualization system, is leading the company and its customers toward level 2 resilient quantum computing. This powerful collaboration will unlock even greater advancements when combined with advanced AI and HPC tools through Azure Quantum.