Surface Code Compilation via Graph-Based Vertex Subset Segmentation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Quantum computing faces challenges in manipulating a large number of qubits beyond their coherence time, requiring error correction methods like surface code architecture to store and manipulate quantum information efficiently, which is computationally intensive.

Innovation Solution

A method is proposed for optimizing the implementation of quantum circuits using a graph-based approach that selects pre-selected subsets of vertices to reduce calculation time, involving the generation of a directed acyclic graph and selecting non-intersecting subsets of rotations to minimize time steps in implementing quantum circuits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Duration of action of stationary object

If quantum error correction using surface code architecture is implemented, then quantum information can be stored and manipulated beyond coherence time, but calculation time and computational resources increase significantly

Engineering Contradiction:
Improvecoherence timeVSAvoidcalculation time
Core Design Contradiction:
Duration of action of stationary objectVSLoss of time

Solution Approach 1:

The quantum circuit is segmented into multiple layers of Pauli rotation gates, and the vertex set is partitioned into pre-selected subsets. This segmentation allows the circuit to be executed in parallel stages, reducing the overall calculation time while maintaining error correction capabilities through the surface code architecture.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The method performs preliminary selection of vertex subsets and construction of associated trees before circuit execution. By pre-identifying non-intersecting subsets and their corresponding trees, the optimization structure is established in advance, enabling faster circuit implementation without compromising the coherence time extension provided by error correction.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If more qubits are manipulated for error correction, then error correction capability improves, but device complexity increases

Engineering Contradiction:
Improveerror correction capabilityVSAvoidcircuit complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The set of vertices is divided into pre-selected subsets, each associated with a separate tree structure. This segmentation organizes the complex qubit interactions into manageable, non-intersecting groups, reducing circuit complexity while maintaining comprehensive error correction coverage across all qubits.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The problem is transformed from selecting individual vertices to selecting subsets of vertices with associated tree structures. This dimensional change in the selection space allows for more efficient organization of qubit operations, reducing the apparent complexity of managing large numbers of qubits for error correction.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Ease of manufacture

If sequential execution of Pauli rotation gates is used, then implementation is straightforward, but calculation time increases

Engineering Contradiction:
Improveimplementation simplicityVSAvoidprocessing speed
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The sequence of Pauli rotation gates is segmented into parallel executable layers based on the pre-selected vertex subsets. Each layer can be executed simultaneously, transforming the sequential implementation into a parallel architecture that maintains simplicity while dramatically improving processing speed.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The method dynamically determines the optimal parallel execution structure by analyzing vertex relationships and constructing trees. This dynamic approach adapts the circuit implementation to maximize parallelism while maintaining the straightforward execution model, improving productivity without sacrificing implementation simplicity.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS20230297867A1Compilation technique for surface code architecture
Publication Date: 2023.09.21 BULL SA
  • US20230297867A1 patent drawing
  • US20230297867A1 patent drawing
  • US20230297867A1 patent drawing

AI summary

Method for implementing a graph (G) comprising a plurality of vertices (V) and links (E) between the vertices, a set (R) being a collection of subsets (Ri) of said a given number of vertices (Rik) comprising:in said set (R), selecting subsets (Ri, Rj), called pre-selected subsets, such that a tree (Ti, Tj) is associated respectively to said tree (Ti, Tj), said associated trees (Ti, Tj) being pairwise disjoint;comparing the number of vertices (Rik) associated to each of the pre-selected subset,among the pre-selected subsets, choosing the subset for which the number of vertices is the highest