CHSH Violations using Dynamic Circuits

2025/04/25 by Jean-Baptiste Waring, Waring, Jean-Baptiste, Christophe Père +3
Computer Science · #FOS: Physical sciences #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Physics (quant-ph) #Quantum-Dot Cellular Automata

paper · pdf · doi:10.48550/arxiv.2504.18429

openalex publication_date 2025/04/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Scalable quantum computing relies on high-quality, long-range entanglement, a challenge on noisy, near-term devices. The need for practical insights for near-term algorithm design calls for trade-offs exploration in implementing dynamic circuits on current hardware. In this work, we experimentally compare three CNOT implementations for generating Bell states across varying qubit separations on a 127-qubit IBM Quantum Eagle processor (ibm_quebec): a unitary (SWAP-based) approach, a dynamic approach with mid-circuit measurements and classical feedforward, and a post-processed approach. We use Clauser-Horne-Shimony-Holt (CHSH) inequality violations to quantify entanglement quality. We observe that, beyond 10 qubits, dynamic circuits lead to higher |S| values than the unitary approach, demonstrating improved distance-dependent entanglement preservation. The post-processed approach yields the highest CHSH values, reaching |S| > 2 up to 13 qubits. Our results underscore the critical need for faster classical feedforward and higher readout fidelity.

Citations

• AC/DC: Automated Compilation for Dynamic Circuits
• Achieving computational gains with quantum error-correction primitives: Generation of long-range entanglement enhanced by error detection
• Practical and efficient quantum circuit synthesis and transpiling with Reinforcement Learning
• Quantum Fourier Transform using Dynamic Circuits
• Exploiting dynamic quantum circuits in a quantum algorithm with superconducting qubits
• Decoherence benchmarking of superconducting qubits
• Tackling the Qubit Mapping Problem for NISQ-Era Quantum Devices
• Violating Bell's inequality with remotely-connected superconducting qubits
• Quantum Computing in the NISQ era and beyond
• A 2D Nearest-Neighbor Quantum Architecture for Factoring in Polylogarithmic Depth
• An introduction to measurement based quantum computation
• Measurement-based quantum computation with cluster states
• Quantum Circuits with Unbounded Fan-out
• Demonstrating the viability of universal quantum computation using teleportation and single-qubit operations
• Dynamical Decoupling of Open Quantum Systems
• On the Einstein Podolsky Rosen paradox
• Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?

Related

• Achieving computational gains with quantum error-correction primitives: Generation of long-range entanglement enhanced by error detection
• Efficient Quantum Circuit Compilation for Near-Term Quantum Advantage
• Quantum Fourier Transform using Dynamic Circuits
• Experimental demonstration of the Bell-type inequalities for four qubit Dicke state using IBM Quantum Processing Units
• Immense Fidelity Enhancement of Encoded Quantum Bell Pairs at Short and Long-distance Communication along with Generalized Design of Circuit