Quantum Bit Microwave Frequency Adjustment Against Clock Harmonics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Harmonic noise generated by digital signals is superimposed on microwaves in quantum computers, leading to potential malfunctions and reduced signal-to-noise ratio (SNR) in quantum bit devices.
Innovation Solution
An information processing apparatus with an adjustment circuit that adjusts the frequency of microwaves to avoid harmonics, using a phase-locked loop (PLL) and local oscillators to ensure the microwaves' frequencies do not match integral multiples of the digital circuit's clock frequency, thereby reducing harmonic noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If digital signals are generated in the quantum computer, then control operations can be performed, but harmonic noise is generated and superimposed on the microwaves
Solution Approach 1:
The patent applies parameter changes by adjusting the frequency of the microwave signal to avoid integer multiples of the digital circuit clock frequency. The frequency adjustment circuit modifies the microwave frequency parameter so that it does not coincide with harmonic frequencies generated by the digital signals, thereby eliminating noise superposition while maintaining control functionality.
2Object-generated harmful factors
If the frequency of microwaves is adjusted to avoid harmonics, then harmonic noise is reduced, but the device complexity increases
Solution Approach 1:
The patent introduces a frequency adjustment circuit as an intermediary component between the signal generation unit and the quantum bit control line. This intermediary device specifically targets and eliminates harmonic noise by adjusting the microwave frequency, while the control signal generation unit continues to operate independently without requiring fundamental design changes.
3Measurement precision
If frequency adjustment is performed to reduce harmonic noise, then signal-to-noise ratio is improved, but power consumption increases
Solution Approach 1:
The patent implements partial action by performing frequency adjustment only when harmonic noise is detected or when operating in specific modes, rather than continuously adjusting the frequency. The frequency adjustment circuit operates selectively to reduce noise while minimizing unnecessary power consumption during normal operation without noise interference.
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
Reduces harmonic noise superimposed on microwaves, maintaining a high SNR and preventing malfunctions in quantum bit devices, while minimizing power consumption and preserving the dynamic range of digital-to-analog converters.
Implementation Method 1
using a phase-locked loop (PLL) and local oscillators to ensure the microwaves' frequencies do not match integral multiples of the digital circuit's clock frequency
Implementation Method 2
using a phase-locked loop (PLL) and local oscillators to ensure the microwaves' frequencies do not match integral multiples of the digital circuit's clock frequency
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An information processing apparatus includes: a quantum bit; a digital circuit configured to generate a digital signal; a conversion circuit configured to convert the digital signal into a microwave to be transmitted to the quantum bit; and an adjustment circuit configured to set a first frequency of a clock used in the digital circuit such that a harmonic frequency of the first frequency differs from a second frequency of the microwave.