Efficient RF to DC Conversion for Scalable Quantum Computing
Here’s PatSnap Eureka !
Summary
Problems
Current methods for applying fast flux bias in quantum computation, such as using room temperature GS/s DACs and static flux bias via cold resistors, suffer from pulse shape distortion, require large voltage DACs, and result in linear scaling of room temperature wiring and heat load, making them unsuitable for large-scale quantum computing applications.
Innovation solutions
A radio-frequency (RF) to direct current (DC) converter system utilizing Josephson junctions and induction lines to convert RF current to single flux quantum (SFQ) pulses, allowing direct application or coupling as flux via mutual inductors, with a bipolar quantized supercurrent generator (QSG) for efficient flux biasing of multiple devices with minimal heat load.
TRIZ Analysis
Specific contradictions:
General conflict description:
Principle concept:
If room temperature GS/s DACs are used to generate fast flux bias pulses, then precise pulse amplitude control is achieved, but large pulse shape distortion occurs due to multiple temperature stages and filtering
Why choose this principle:
The patent introduces a cold resistor at 4K as an intermediary component between the room temperature DAC and the quantum device. This cold resistor generates the actual bias current locally at the device temperature, eliminating the need for signal transmission through multiple temperature stages and filtering, thus preserving pulse shape fidelity while maintaining amplitude precision through digital control
Principle concept:
If room temperature GS/s DACs are used to generate fast flux bias pulses, then precise pulse amplitude control is achieved, but large pulse shape distortion occurs due to multiple temperature stages and filtering
Why choose this principle:
The patent replaces the traditional room-temperature resistive biasing system with a superconducting quantum interference device (SQUID)-based flux bias system. This substitution enables direct magnetic flux coupling to the quantum device, eliminating the need for physical wiring through temperature stages and reducing pulse distortion
Application Domain
Data Source
AI summary:
A radio-frequency (RF) to direct current (DC) converter system utilizing Josephson junctions and induction lines to convert RF current to single flux quantum (SFQ) pulses, allowing direct application or coupling as flux via mutual inductors, with a bipolar quantized supercurrent generator (QSG) for efficient flux biasing of multiple devices with minimal heat load.
Abstract
A radio-frequency (RF) to direct current (DC) converter is provided. When a DC electrical current is applied via a DC input port of the converter, the DC electrical current is shunted to ground through a Josephson junction (JJ) of the converter and substantially no DC electrical current flows through a resistor of the converter, and when an RF electrical current is applied via an RF input port of the converter, output trains of SFQ current pulses from a DC to SFQ converter of the RF-to-DC converter with pulse-to-pulse spacing inversely proportional to the RF electrical current frequency cause the JJ to switch at a rate commensurate with an RF frequency of the RF electrical current to generate a steady state voltage across the JJ linearly dependent on the RF frequency.