Microsoft and Atom Computing have announced what they claim is a significant step forward in reliable quantum computing, unveiling a commercial quantum machine built with 24 entangled logical qubits.
The system, achieved through a combination of Atom Computing’s neutral-atom hardware and Microsoft’s qubit-virtualization technology, aims to address the critical challenge of error detection and correction in quantum computation.
The quantum machine, available for order today with delivery expected in 2025, is part of Microsoft’s Azure Quantum platform and integrates with its Azure Elements suite. Together, the technologies are designed to provide a more stable and dependable environment for quantum applications in fields such as artificial intelligence, chemistry and materials science, the companies said in a joint statement at Microsoft Ignite 2024.
“By coupling our state-of-the-art neutral-atom qubits with Microsoft’s qubit-virtualization system, we are now able to offer reliable logical qubits on a commercial quantum machine,” Ben Bloom, founder and CEO of Atom Computing, said in the announcement. “This system will enable rapid progress in multiple fields including chemistry and materials science.”
In quantum computing, physical qubits are the fundamental building blocks used to encode quantum information, typically implemented using physical systems like trapped ions, superconducting circuits, or neutral atoms.
However, physical qubits are prone to errors caused by environmental noise, hardware imperfections, and quantum decoherence.
To address these challenges, multiple physical qubits are combined to form logical qubits, which leverage quantum error-correction techniques to detect and mitigate errors during computation.
Logical qubits play a critical role in enabling reliable quantum computing, as they provide the stability and precision necessary for performing complex algorithms and achieving practical quantum advantage in real-world applications.
“Error correction, stability, and scalability are crucial for reliable quantum computations to address real-world applications, and logical qubits are more stable and less error-prone than physical qubits,” said Charlie Dai, VP, principal analyst at Forrester. “This achievement demonstrates substantial progress in such direction towards quantum advantage.”
Neutral-atom qubits as the foundation
Atom Computing uses neutral atoms manipulated by laser pulses to store and process quantum information. According to the companies, this design provides advantages over other qubit technologies, including scalability and reduced noise sensitivity, which are critical for error correction.
Microsoft’s qubit-virtualization system builds on these physical qubits to create logical ones, enabling more stable quantum operations. “Reliable quantum computing requires qubits that can detect and correct errors during computations,” the company noted in a blog post.
The machine’s reliability stems from achieving a two-qubit gate fidelity of 99.6% and the ability to detect and correct errors, even when qubit losses occur. The teams created 24 logical qubits and entangled them in a Greenberger-Horne-Zeilinger (GHZ) state, which the companies claim represents the highest number of entangled logical qubits on record.
Developments in reliable quantum computing
This achievement builds on Microsoft’s earlier collaborations in quantum computing. In September 2024, Microsoft and Quantinuum applied Azure Quantum’s qubit-virtualization system to Quantinuum’s H2 trapped-ion quantum computer, creating 12 highly reliable logical qubits.
The teams demonstrated the potential of hybrid quantum-classical computing by using two logical qubits, integrated with AI models and cloud high-performance computing (HPC), to estimate the ground state energy of a catalytic intermediate.
At the time, Microsoft and Quantinuum also showcased advancements in error correction, creating logical qubits with error rates 800 times better than the underlying physical qubits. This was achieved by expanding Microsoft’s error-correction algorithms and optimizing them for Quantinuum’s H2 machine, which features 56 qubits with 99.8% two-qubit fidelity.
By entangling 12 logical qubits in a cat state, the teams further demonstrated the potential of logical qubits in practical applications, paving the way for today’s progress with 24 entangled logical qubits.
These consistent advancements reflect Microsoft’s focus on achieving scientific quantum advantage, where quantum systems solve problems that classical computers cannot.
Azure Quantum’s role in reliable computation
Microsoft and Atom Computing’s quantum machine operates on the Azure Quantum compute platform, which combines hardware and software to prioritize dependable quantum computation. This approach aims to ensure customers can use the system for stable and repeatable calculations while integrating with Azure Elements for additional capabilities such as AI-driven tools and high-performance computing.
By coupling logical qubits with cloud resources, the system could accelerate research in quantum chemistry and materials science while opening doors to new applications, the statement added.
Reliability vs speed
While Microsoft and Atom Computing focus on enhancing reliability with their 24 entangled logical qubits system, IBM is advancing the scale and speed of quantum computations.
At its inaugural IBM Quantum Developer Conference last week, IBM unveiled its most advanced quantum processor to date, Quantum Heron, capable of executing up to 5,000 two-qubit gate operations — nearly double the benchmark set last year. Leveraging its Qiskit software platform, IBM achieved a 50-fold reduction in computation time for complex quantum experiments compared to its 2023 milestones.
This underscores the contrasting priorities in the quantum race. Microsoft’s system emphasizes error correction and qubit reliability, aiming to create stable logical qubits for dependable quantum operations. In contrast, IBM’s Quantum Heron focuses on scalability and computational speed, pushing the boundaries of quantum utility in fields like materials science and life sciences.
Both approaches represent significant strides, but they highlight distinct pathways toward realizing quantum advantage — IBM advancing quantum utility through sheer scale and speed, and Microsoft through reliable computation.
The emphasis on reliability distinguishes this offering in a field where error-prone systems remain a challenge. IBM and Google have developed competing quantum technologies, such as superconducting qubits, but their systems often contend with higher noise levels, limiting scalability and stability.
Neutral-atom qubits, according to Atom Computing, have inherent advantages, including scalability through compact arrays and lower noise susceptibility, making them better suited for error correction.
While Microsoft and Atom Computing claim their machine offers a more reliable solution, achieving widespread adoption of quantum systems will require continued improvements in both hardware and software.
“Tech giants are taking various tech routes, such as IBM’s highly efficient quantum error-correcting codes and co-designing error-correcting codes with their hardware, as well as Google’s surface codes with real-time decoders, leakage mitigation, and stabilizer codes for exponential error suppression,” Dai pointed out.
As the race to develop practical quantum computing intensifies, the ability to offer reliable systems could become a key differentiator. The commercial success of these systems will depend not only on their technical performance but also on how effectively they meet real-world needs across industries. According to Dai the tech majors “are all making significant contributions to the field with their unique approaches to error detection and correction, paving the way to practical, fault-tolerant quantum computing.”
Source:: Network World