Atomique: A Scalable Quantum Compiler for Reconfigurable Neutral Atom Arrays

Core Concepts

Atomique, a scalable compilation framework for reconfigurable neutral atom arrays (RAAs), efficiently maps qubits, schedules atom movements, and executes gates to minimize circuit depth and two-qubit gate count while respecting hardware constraints.

Abstract

The paper introduces Atomique, a scalable compilation framework for reconfigurable neutral atom arrays (RAAs). RAAs feature both fixed atoms (realized using spatial light modulators) and movable atoms (realized using acousto-optic deflectors), allowing for dynamic qubit coupling during circuit execution.
The key aspects of Atomique are:

Qubit-Array Mapper: This module decides the assignment of qubits to different atom arrays to maximize the number of directly executable two-qubit gates between arrays, minimizing the need for costly SWAP operations.

Qubit-Atom Mapper: This module maps qubits to specific atom positions within each array, considering load balancing and preserving the order of rows/columns to enable parallel gate execution.

High-Parallelism Router: This module iteratively identifies independent gates, schedules them in parallel, and performs the necessary atom movements and laser activations while respecting hardware constraints.

Atomique extensively models the overhead of atom movements, including heating, cooling, decoherence, and atom loss, to accurately estimate the circuit fidelity. Compared to prior approaches, Atomique achieves significant reductions in circuit depth and two-qubit gate count across a diverse set of benchmarks, including generic circuits, quantum simulation, and QAOA circuits. It also demonstrates 1000x faster compilation times than a previous solver-based approach.

Stats

The neutral atom array has a two-qubit gate fidelity of 0.9975 and a one-qubit gate fidelity of 0.99992.
The coherence time (T1) of the neutral atom system is 15 seconds.
The time for a single atom movement is 300 microseconds, and the time for atom transfer between SLM and AOD is 15 microseconds.
The atom loss probability during movement is 0.0068.

Quotes

"The neutral atom array has gained prominence in quantum computing for its scalability and operation fidelity."
"RAA's AOD movements are high-fidelity, limited primarily by coherence time. Ref. [10] estimates that with only 0.1% of coherence time lost, an AOD array could traverse a region hosting ∼2, 000 qubits."
"When nvib <
2
λ ≈18, which corresponds to fewer than 1000 gates, we expect better performance using RAA atom movement, since the overhead of movement will be less than that of additional SWAP gates."

Key Insights Distilled From

Atomique: A Quantum Compiler for Reconfigurable Neutral Atom Arrays

by Hanrui Wang,... at arxiv.org 05-03-2024

https://arxiv.org/pdf/2311.15123.pdf

Deeper Inquiries

How can Atomique's compilation techniques be extended to other quantum hardware architectures beyond neutral atom arrays

Atomique's compilation techniques can be extended to other quantum hardware architectures by adapting the mapping and routing strategies to suit the specific characteristics of different platforms. For example, the qubit-array mapper and qubit-atom mapper can be modified to accommodate the connectivity constraints and gate operations of superconducting qubits or trapped ions. The high-parallelism router can be adjusted to optimize gate scheduling and movement strategies based on the unique features of each hardware architecture. By customizing these components, Atomique's compilation framework can be applied to a wide range of quantum computing systems, enabling efficient qubit mapping, gate scheduling, and atom movement for improved performance and fidelity.

What are the potential limitations or drawbacks of the reconfigurable atom array (RAA) approach compared to other quantum computing platforms

While the reconfigurable atom array (RAA) approach offers advantages such as dynamic qubit connectivity and reduced SWAP gate overhead, it also has potential limitations compared to other quantum computing platforms. Some drawbacks of the RAA approach include:

Complexity of Atom Movement: Managing atom movements and transfers in real-time can be challenging and may introduce errors or inefficiencies in the quantum circuit execution.
Atom Loss and Heating: The heating and atom loss associated with atom movements can impact the overall fidelity of the quantum operations, leading to potential errors and reduced performance.
Hardware Constraints: The constraints on AOD arrays, such as row/column orders and overlap restrictions, can limit the flexibility and scalability of the RAA architecture, especially in larger quantum systems.
Decoherence Effects: The decoherence effects during atom movements and transfers can introduce additional errors and reduce the overall fidelity of the quantum computations.

How can the atom movement and transfer overhead modeling in Atomique be further improved to better capture the complex dynamics and error sources in neutral atom systems

To enhance the atom movement and transfer overhead modeling in Atomique for neutral atom systems, several improvements can be considered:

Dynamic Heating and Loss Models: Develop more sophisticated models that dynamically adjust heating and loss probabilities based on the specific characteristics of the atoms and the movement patterns. This can provide a more accurate representation of the impact of atom movements on fidelity.
Real-time Error Correction: Implement real-time error correction mechanisms to mitigate the effects of heating, loss, and decoherence during atom movements. This can help improve the overall fidelity of the quantum computations.
Optimized Cooling Strategies: Explore optimized cooling strategies to minimize the impact of heating and loss during atom transfers. By efficiently managing the cooling process, the overhead of atom movements can be reduced.
Integration of Machine Learning: Incorporate machine learning algorithms to predict and optimize atom movement trajectories, taking into account various error sources and constraints. This can lead to more efficient and accurate atom movement planning in Atomique.