Encoded Logical Qubits With Passive Noise Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing quantum computing technologies face challenges in protecting quantum information from noise during computation, which can lead to errors and reduce the reliability of quantum operations.
Innovation Solution
The method involves creating encoded quantum bits using a two-dimensional lattice of physical qubits, where neighbors are strongly coupled through two-qubit interactions. This forms a composite logical qubit that is protected from noise by coupling and decoupling multiple composite qubits and applying local fields, all of which are controlled adiabatically.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If quantum operations are performed without noise suppression, then device complexity is reduced, but reliability of quantum operations deteriorates due to noise-induced errors
Solution Approach 1:
The quantum system is segmented into multiple physical qubits that are coupled together to form a single logical qubit. This segmentation allows the quantum information to be distributed across multiple physical components, providing redundancy and noise suppression capability while maintaining the functional integrity of the quantum operation.
Solution Approach 2:
The patent implements a nested structure where physical qubits are nested within logical qubits. Multiple physical qubits are coupled and organized to form a composite logical qubit, creating a hierarchical structure that embeds the quantum information at different levels of organization. This nesting enables error suppression by distributing quantum states across the nested physical components.
2Object-affected harmful factors
If encoded quantum bits are created using multiple physical qubits, then noise suppression is improved, but device complexity increases due to additional coupling mechanisms
Solution Approach 1:
Multiple physical qubits are merged and strongly coupled together to function as a single logical qubit. The coupling mechanisms between neighboring physical qubits are designed to create unified quantum states across the group, effectively combining their computational power while providing collective noise suppression. This merging approach suppresses noise by distributing quantum information across the combined physical components.
3Reliability
If adiabatic control is applied to coupling and decoupling operations, then reliability of quantum gates is improved, but speed of quantum operations deteriorates due to gradual Hamiltonian interpolation
Solution Approach 1:
The patent employs dynamic control of the Hamiltonian evolution, using adiabatic interpolation to gradually transition between different quantum states and gate operations. This dynamic approach allows the system to maintain reliability by avoiding abrupt changes that could induce errors, while the controlled rate of change ensures that the quantum gates complete their operations within acceptable timeframes.
Data Source
Figure 1~5
Figure 2
Figure 3~4
AI summary
Systems and methods are provided for performing noise-resilient quantum operations. A set of control signals are applied to a system to provide a first Hamiltonian for the system. The system includes an array of physical qubits and a plurality of coupling mechanisms configured such that each pair of neighboring physical qubits within the array is coupled by an associated coupling mechanism. The first Hamiltonian represents, for each coupling mechanism, a coupling strength between zero and a maximum value. An adiabatic interpolation of the Hamiltonian of the system from the first Hamiltonian to a second Hamiltonian is performed. The second Hamiltonian represents, for at least one of the plurality of coupling mechanisms, a coupling strength different from that of the first Hamiltonian.