Operator Averaging in Quantum Computing Systems

Solution Overview

Problem

Current quantum computing algorithms require a large number of state preparation and measurement repetitions to estimate expectation values of operators, which is computationally inefficient and resource-intensive.

Innovation Solution

The method involves identifying a first operator associated with a quantum mechanical observable, determining constraints on its expectation values, defining a second operator that combines the first operator with these constraints, and estimating the expectation value using the second operator, thereby reducing the number of measurements required.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional state preparation and measurement repetitions are used to estimate expectation values, then measurement precision is achieved, but the number of repetitions required becomes excessively large, increasing computational time and resource consumption

Engineering Contradiction:

Improveexpectation value estimation precisionVSAvoidcomputational time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent introduces constraint operators as intermediaries that encode physical laws and symmetries of the quantum system. These constraint operators mediate between the observable operator and the measurement process, enabling the use of symmetry information to reduce the number of measurements required while maintaining precision in expectation value estimation.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the parameters of the measurement process by incorporating constraint operators into the measurement protocol. By modifying the measurement approach to include constraint information, the method reduces the number of repetitions needed from the traditional scaling to a reduced scaling, thereby decreasing computational time while preserving measurement precision.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If traditional state preparation and measurement repetitions are used to estimate expectation values, then measurement precision is achieved, but resource requirements increase

Engineering Contradiction:

Improveexpectation value estimation precisionVSAvoidnumber of measurement repetitions

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent introduces constraint operators as intermediaries that encode physical laws and symmetries of the quantum system. These constraint operators mediate between the observable operator and the measurement process, enabling the use of symmetry information to reduce the number of measurements required while maintaining precision in expectation value estimation.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the parameters of the measurement process by incorporating constraint operators into the measurement protocol. By modifying the measurement approach to include constraint information, the method reduces the number of repetitions needed from the traditional scaling to a reduced scaling, thereby decreasing computational time while preserving measurement precision.

Inventive Principle:

Principle #35Parameter changes

3Productivity

If more constraint operators are incorporated into the measurement process, then the number of measurement repetitions is reduced, but the complexity of the measurement protocol increases

Engineering Contradiction:

Improvecomputational efficiencyVSAvoidmeasurement protocol complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent introduces constraint operators as intermediaries that encode physical laws and symmetries of the quantum system. These constraint operators mediate between the observable operator and the measurement process, enabling the use of symmetry information to reduce the number of measurements required while maintaining precision in expectation value estimation.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent segments the measurement protocol into distinct components: the observable operator, the constraint operators, and the measurement process. This segmentation allows for modular implementation where constraint operators can be systematically incorporated without overwhelming complexity, as each constraint can be handled independently in the measurement protocol.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS20250045357A1Operator averaging within quantum computing systems

Publication Date: 2025.02.06 GOOGLE LLC

AI summary

Methods, systems and apparatus for estimating an expectation value of a quantum mechanical observable. In one aspect, a method includes identifying a first operator associated with the observable, wherein the first operator comprises a linear combination of terms. One or more constraints on expectation values of one or more of the terms in the linear combination are determined. A second operator is defined, wherein the second operator comprises a combination of the first operator and one or more of the determined constraints. The expectation value of the quantum mechanical observable is estimated using the second operator.