🤖 AI Summary
Conventional fault-tolerant quantum computation employs gate-level logical synthesis to implement Trotter steps sequentially, resulting in high resource overhead and neglecting the global structure of quantum algorithms.
Method: We propose the “monolithic logical Trotter circuit” framework, which executes the full Hamiltonian simulation circuit directly within a single stabilizer code block—bypassing gate-level synthesis. Our approach integrates stabilizer encoding, symplectic geometry, Trotter decomposition, and bias-tailored fault tolerance, supporting codes including the [[8,3,3]] code and quantum LDPC codes.
Contribution/Results: We establish, for the first time, a structural mapping between symplectic scaling transformations and Trotter circuits, ensuring logical–physical circuit isomorphism, centralized stabilizer preservation, and symmetry maintenance under non-Clifford rotations. Experiments demonstrate substantial reduction in fault-tolerant resource overhead and enable Hamiltonian simulation for arbitrary rotation angles—introducing a new paradigm for algorithm-aware, customized fault-tolerant design.
📝 Abstract
Conventional approaches to fault-tolerant quantum computing realize logical circuits gate-by-gate, synthesizing each gate independently on one or more code blocks. This incurs excess overhead and doesn't leverage common structures in quantum algorithms. In contrast, we propose a framework that enables the execution of entire logical circuit blocks at once, preserving their global structure. This whole-block approach allows for the direct implementation of logical Trotter circuits - of arbitrary rotation angles - on any stabilizer code, providing a powerful new method for fault tolerant Hamiltonian simulation within a single code block. At the heart of our approach lies a deep structural correspondence between symplectic transvections and Trotter circuits. This connection enables both logical and physical circuits to share the Trotter structure while preserving stabilizer centralization and circuit symmetry even in the presence of non-Clifford rotations. We discuss potential approaches to fault tolerance via biased noise and code concatenation. While we illustrate the key principles using a $[[8,3,3]]$ code, our simulations show that the framework applies to Hamiltonian simulation on even good quantum LDPC codes. These results open the door to new algorithm-tailored, block-level strategies for fault tolerant circuit design, especially in quantum simulation.