Josephson Junction With Ferromagnetic Polarizers

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current methods for controlling Josephson junctions in fast logic circuits are energy-inefficient and limited in their ability to switch between active and inactive modes, restricting their applications due to reliance on voltage or current bias and energy dissipation.

Innovation Solution

A Josephson junction component with ferromagnetic polarizers and an intermediate conductive layer, utilizing the Andreev effect to control unconventional supercurrents, allowing for magnetic field-induced switching between on and off states, reducing energy dissipation and enabling efficient mode control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If voltage or current bias is used to control Josephson junction switching between active and inactive modes, then the junction can be switched between modes, but energy dissipation increases and control efficiency decreases

Engineering Contradiction:

Improvecontrol efficiencyVSAvoidenergy dissipation

Core Design Contradiction:

Ease of operationVSLoss of energy

Solution Approach 1:

The patent changes the control parameter from voltage/current bias to magnetic field orientation. By rotating the magnetization vector of the ferromagnetic layer between parallel and antiparallel configurations relative to the superconducting layer, the Josephson junction switches between active and inactive modes without requiring continuous voltage or current bias, thereby reducing energy dissipation while maintaining ease of control

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent replaces the electrical control mechanism (voltage/current bias) with a magnetic control mechanism (magnetization orientation). This substitution allows the Josephson junction to be controlled by the orientation of magnetic moments in the ferromagnetic layer, which can be switched using magnetic fields or spin-transfer torque, reducing the energy required for mode switching compared to traditional electrical bias methods

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Ease of operation

If a matrix of Josephson junctions is used to generate control voltage, then control capability is achieved, but energy consumption increases due to permanent active mode operation

Engineering Contradiction:

Improvecontrol capabilityVSAvoidenergy consumption

Core Design Contradiction:

Ease of operationVSUse of energy by moving object

Solution Approach 1:

The patent changes the operational state of individual Josephson junctions from permanently active to switchable between active and inactive modes via magnetic field control. By orienting the magnetization of ferromagnetic layers in different regions, control voltage can be generated locally only where needed, eliminating the requirement for all junctions in the matrix to remain permanently active and thus reducing overall energy consumption

Inventive Principle:

Principle #35Parameter changes

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 solution allows for efficient control of Josephson junctions, reducing energy dissipation and enabling flexible operation modes, thereby expanding their applications in RSFQ circuits and other electronic systems.

Implementation Method 1

A Josephson junction component with ferromagnetic polarizers and an intermediate conductive layer, utilizing the Andreev effect to control unconventional supercurrents

Methodology Applied

Scientific EffectAndreev effect:

Implementation Method 2

In a Josephson junction, although the continuity of the superconducting material is interrupted by the presence of the non-superconducting material of the intermediate layer, there is a coupling between the wave functions of the charge carriers in the first and second superconducting layers

Methodology Applied

Scientific EffectJosephson effect: Josephson Effect

Implementation Method 3

In a superconducting medium, the charge carriers are formed by the association of two electrons, within a Cooper pair. In so-called 'conventional' superconductors, the associated electrons have opposite spins, the Cooper pair then having zero spin

Methodology Applied

Scientific EffectSuperconductivity: Superconductivity

Implementation Method 4

there is a coupling between the wave functions of the charge carriers in the first and second superconducting layers. Indeed, according to the Josephson effect, the wave function of the charge carriers of the first superconducting layer extends through the intermediate layer, into the second superconducting layer

Methodology Applied

Scientific EffectJosephson effect: Josephson Effect

Data Source

PatentEP2945160B1Josephson junction electronic component

Publication Date: 2017.03.15 THALES SA

AI summary

This component (10) comprises first and second layers (1, 5) of a superconducting material, separated from each other by an intermediate layer (3) of an electrically conductive material; and first and second polarizers (2, 4) of a ferromagnetic material, the first polarizer, having a first magnetization (M2), being interposed between the intermediate layer (3) and the first layer (1), and the second polarizer, having a second magnetization (M4), being interposed between the intermediate layer (3) and the second layer (5). It further comprises a control means (12) for modifying at least one of the first and second magnetizations to place the component either in a conducting state in which the first and second magnetizations are parallel to each other, or in a blocking state in which the first and second magnetizations are antiparallel to each other.