Superconducting Quantum Circuit Grounding to Suppress Qubit Crosstalk
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Quantum circuits using superconducting circuits face challenges in completely turning off unnecessary interactions between quantum bits, leading to residual interactions that cause errors and reduce computational accuracy and precision.
Innovation Solution
A superconducting complex quantum computing circuit is designed with a specific configuration including a circuit substrate, ground electrodes, control signal lines, and a pressing member, which uses superconducting extension portions and Josephson junctions to suppress interactions and crosstalk between quantum bits.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional quantum circuit configuration is used, then the circuit can be implemented with standard design, but residual interactions between quantum bits cannot be completely turned off causing control errors
Solution Approach 1:
The ground electrode is segmented into multiple independent ground electrodes positioned at different locations. Each ground electrode is independently connected to the ground pattern through extension portions, allowing separate control and optimization of grounding effects in different regions to suppress residual interactions and crosstalk between quantum bits
Solution Approach 2:
Extension portions made of superconductor material are introduced as intermediary elements connecting the ground electrodes to the ground pattern. These extension portions have higher extensibility than the ground pattern itself, enabling effective grounding connection while accommodating thermal contraction and maintaining reliable electrical contact at cryogenic temperatures
2Measurement precision
If ground electrodes are added to suppress residual interactions, then control accuracy improves, but device structure becomes more complex
Solution Approach 1:
Multiple ground electrodes are merged into a unified grounding system that collectively suppresses residual interactions across the quantum bit array. The extension portions of different ground electrodes are merged with the common ground pattern, creating an integrated grounding network that reduces crosstalk while maintaining modular structure for ease of fabrication
Solution Approach 2:
The extensibility parameter of the connection material is changed by using superconductor material for extension portions, which has higher extensibility than the ground pattern material. This parameter change allows the ground electrodes to maintain reliable electrical contact with the ground pattern under thermal stress at cryogenic temperatures, ensuring stable grounding performance
3Ease of manufacture
If standard grounding is used, then manufacturing is simpler, but crosstalk between quantum bits increases reducing error tolerance
Solution Approach 1:
The grounding approach transitions from a two-dimensional planar connection to a three-dimensional structure by adding vertical extension portions that protrude from the substrate surface. This dimensional change allows ground electrodes to be positioned optimally for suppressing crosstalk while maintaining manufacturability through standard thin-film deposition and lithography processes
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration effectively suppresses interaction and crosstalk between quantum bits, enhancing error tolerance and computational precision by minimizing residual interactions and electromagnetic modes.
Implementation Method 1
a first extension portion formed by a superconductor having extensibility higher than extensibility of the ground pattern, and the second ground electrode is in contact with the ground pattern via a second extension portion formed by a superconductor having extensibility higher than the extensibility of the ground pattern
Implementation Method 2
a pressing member that presses the first ground electrode against the first surface of the circuit substrate or presses the second ground electrode against the second surface of the circuit substrate
Data Source
AI summary
A superconducting complex quantum computing circuit includes a circuit substrate in which a wiring pattern of a circuit element including quantum bits and measurement electrodes, and ground patterns are formed, and through-electrodes connecting the ground pattern formed on a first surface of the substrate surface and the ground pattern formed on a second surface; a first ground electrode including a first contact portion in contact with the ground patterns, and a first non-contact portion having a shape corresponding to a shape of the wiring pattern; a second ground electrode including a second contact portion in contact with the ground pattern; a control signal line provided with a contact spring pin at a tip; and a pressing member that presses the first ground electrode against the first surface of the circuit substrate or presses the second ground electrode against the second surface of the circuit substrate.