Cryostat Clock Generation for Photonic Quantum Timing Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Photonic quantum computers require accurate clock signals for precise timing control of optical elements, but existing methods face challenges due to random phase errors and non-deterministic nature of heralding signals, making it difficult to generate suitable clock signals for photonic quantum computing systems.
Innovation Solution
A system and method for generating clock signals for photonic quantum computing systems, where a pump photon source outside a cryostat generates pulses that are converted into photon pairs inside the cryostat, with excess pump photons being used to create electrical pulses for a clock generator, ensuring synchronization and reducing phase errors by local generation within the cryostat.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If clock signals are generated outside the cryostat using pump photon source, then the system structure is simpler, but random phase errors increase and timing precision deteriorates
Solution Approach 1:
The patent introduces an intermediary clock generation system located inside the cryostat that converts pump photon pulses into electrical clock signals. This intermediary system acts as a mediator between the external pump source and the internal quantum computing operations, allowing clock signals to be generated at the appropriate location while maintaining synchronization with the pump pulse timing.
Solution Approach 2:
The patent replaces the conventional mechanical/electrical clock generation system with an optical-based system. Instead of using traditional electrical oscillators or mechanical timers, the system uses photodetectors to convert optical pump pulses directly into electrical clock signals, substituting optical processes for conventional electrical/mechanical timing mechanisms.
2Reliability
If heralding signals are used for clock generation, then photon detection is enabled, but non-deterministic nature causes phase errors
Solution Approach 1:
The patent extracts the clock signal generation function from the heralding signal path. Instead of using heralding signals (which are non-deterministic) for timing, the system separately extracts a portion of the pump photons to generate deterministic clock signals. This separation allows photon detection to proceed using heralding signals while timing is controlled by the extracted pump photon subset.
Solution Approach 2:
The system performs preliminary action by pre-establishing a deterministic clock signal generation mechanism based on pump photon timing. The photodetector is positioned to receive pump photons before they enter the nonlinear crystal, allowing the clock signals to be generated in advance and providing a stable timing reference for the subsequent quantum computing operations.
3Loss of time
If photodetector is placed inside the cryostat to receive pump photons, then clock signal synchronization is improved, but the system requires more components inside the cryostat
Solution Approach 1:
The patent applies multi-functionality by using the same cryostat environment to house both the quantum computing components and the clock generation components. The photodetector, waveguide, and other clock generation elements serve dual purposes: they enable timing synchronization while coexisting with the quantum computing operations within the same cryogenic environment, reducing the need for separate external timing systems.
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 approach provides stable and synchronized clock signals with reduced phase errors, essential for precise timing in photonic quantum computers, preventing random phase errors and ensuring high performance by utilizing excess pump photons for clock generation within the cryostat.
Implementation Method 1
a photodetector disposed inside the cryostat and configured to receive the second portion of each pump photon pulse of the plurality of pump photon pulses generate a plurality of electrical pulses by converting the second portion of each pump photon pulse of the plurality of pump photon pulses into a respective electrical pulse of the plurality of electrical pulses
Implementation Method 2
a photon-pair source disposed inside the cryostat and optically coupled to the first waveguide. The photon-pair source is configured to receive the plurality of pump photon pulses via the waveguide, convert a first portion of each of a subset of the plurality of pump photon pulses into a photon pair
Data Source
AI summary
A system for generating clock signals for a photonic quantum computing system includes a pump photon source configured to generate a plurality of pump photon pulses at a first repetition rate, a waveguide optically coupled to the pump photon source, and a photon-pair source optically coupled to the first waveguide. The system also includes a photodetector optically coupled to the photon-pair source and configured to generate a plurality of electrical pulses in response to detection of at least a portion of the plurality of pump photon pulses at the first repetition rate and a clock generator coupled to the photodetector and configured to convert the plurality of electrical pulses into a plurality of clock signals at the first repetition rate.