Neutral Atom QPU From Infleqtion Demonstrates In-Place Entanglement with 114 Qubits

Neutral atoms represent a promising platform for building powerful quantum computers, but achieving practical scalability requires overcoming challenges in how qubits interact and become entangled. Rich Rines, Benjamin Hall, Mariesa H. Teo, and colleagues at Infleqtion have now demonstrated a novel quantum architecture that significantly reduces the need for qubit movement during computations. The team successfully implements key quantum algorithms, including a logical qubit version of Shor’s algorithm, and showcases a constant-depth technique for performing CNOT gates, achieving approximately four times lower error rates with logical encodings. Furthermore, they experimentally realise initialisation of a complex error-correcting code, the [[16, 4, 4]] many-hypercube code, all benefiting from the new architecture’s ability to unite qubit motion with in-place entanglement, paving the way for more efficient and scalable quantum computing.

Neutral Atom Qubit Control and Measurement

Neutral atom quantum computing is rapidly emerging as a leading platform for building powerful quantum computers. Researchers are making significant progress in overcoming the challenges of scaling up these systems and achieving reliable computation, with a central focus on fault tolerance, the ability to protect quantum information from errors. While full fault tolerance remains a long-term goal, scientists are also developing error mitigation techniques to improve the performance of near-term quantum devices. A key challenge lies in maintaining high connectivity between qubits as the number of qubits increases, and researchers are exploring innovative architectures and techniques to address this, leveraging the unique characteristics of neutral atom systems to simplify fault tolerance and improve performance.

Surface codes remain a prominent approach to fault-tolerant quantum computation, benefiting from their relatively high threshold and suitability for two-dimensional architectures. Scientists continue to refine decoding algorithms and reduce the overhead associated with these codes, adapting them to the specific characteristics of neutral atom hardware. Low-Density Parity-Check (LDPC) codes are gaining traction as a potentially more efficient alternative, offering lower overhead and faster decoding, though they require more complex hardware. Researchers are also exploring different topological codes beyond surface codes to further improve performance and reduce overhead, with innovative approaches leveraging atom loss as a resource for error correction.

Combining different codes through concatenation offers higher levels of error protection, while dynamic circuit design adapts to the specific error characteristics of the hardware. Hardware-specific techniques are also crucial, utilizing strong, long-range interactions between Rydberg atoms to create highly connected qubit arrays. Optical tweezers trap and manipulate individual atoms, creating arbitrary qubit arrangements, and employing dual-species arrays enhances robustness and versatility. Dynamic reconfiguration allows qubits to be moved and rearranged during computation, enabling more complex circuits and improved performance.

Developing techniques for long-range connectivity reduces the need for complex routing and improves scalability. Error mitigation techniques, such as zero-noise extrapolation and probabilistic error cancellation, further enhance the performance of quantum computations, while efficient gate decomposition and circuit scheduling optimize quantum circuits. The most promising approaches involve designing error-correcting codes tailored to the specific characteristics of the hardware. Error mitigation techniques improve near-term quantum computers, while fault tolerance is essential for long-term reliability. Optimizing quantum circuits reduces the number of gates and the overall error rate, simplifying error correction. Future research will focus on scaling up qubit arrays, improving qubit coherence, developing more efficient error-correcting codes, and automating quantum compilation.

Shor’s Algorithm Runs on Logical Qubits

Scientists have achieved a significant breakthrough by demonstrating a new quantum computing architecture that unifies qubit motion with in-place entanglement. Realized on a system hosting 114 neutral atom qubits, this architecture minimizes qubit movement, a common source of error, while maintaining full connectivity. The team successfully demonstrated a logical qubit realization of Shor’s Algorithm, revealing improved logical-over-physical performance, and introduced a novel technique for performing CNOT ladders with a depth independent of the number of logical qubits. They also experimentally realized the initialization of a promising quantum error correction code. These results benefit from optimized compilation and the architecture’s ability to unite motion and in-place entanglement, demonstrating a path toward reducing the overhead of utility-scale quantum applications.

Neutral Atom Qubits Demonstrate In-Place Entanglement

This research demonstrates a novel quantum computing architecture utilizing neutral atoms, which unifies qubit motion with in-place entanglement, addressing a key limitation of previous designs. Experimentally realized on a system hosting 114 neutral atom qubits, this architecture achieves improved logical-over-physical performance in demonstrations of logical circuits. These results stem from compiler-level transformations optimizing qubit placement to minimize movement, and the implementation of in-place operations that enable faster, more accurate entanglement. The researchers successfully implemented a quantum error correction code and demonstrated a reduction in error rates using logical encodings. This architecture prioritizes qubit count over native gate speed, a strategy well-suited to neutral atom systems. Future work will focus on extending the system and developing motion-aware compilers to scale these paradigms to larger systems, ultimately laying the groundwork for substantial increases in scale towards large, fault-tolerant quantum computers.