Superconducting Cap Sensor for Non-Contact Cryogenic Thermal Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current thermal scanning microscopy techniques require direct physical contact with the substrate, which can interfere with the system's characteristics, damage the sample, and are limited in temperature resolution and operability at low temperatures.
Innovation Solution
A non-contact thermal measurement device using a superconductive cap with electrically conductive leads that transmit electrical current to determine temperature variations without physical contact, allowing for high-resolution thermal imaging at cryogenic temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If direct physical contact between probe and substrate is used for thermal measurement, then temperature measurement capability is achieved, but sample damage and system characteristic interference occur
Solution Approach 1:
The patent introduces a superconductive tip as an intermediary element that enables thermal measurement without direct physical contact with the substrate. The tip utilizes superconductive properties to detect temperature variations through near-field thermal coupling, acting as a mediator between the measurement system and the sample, thereby achieving temperature measurement capability while avoiding sample damage and system interference associated with direct contact methods
2Measurement precision
If conventional thermal scanning microscopy is used, then thermal mapping is achieved, but temperature resolution is limited and low temperature operability is restricted
Solution Approach 1:
The patent changes the operational parameters of the measurement system by utilizing superconductive materials that exhibit enhanced thermal sensitivity at cryogenic temperatures. The superconductive tip's critical current and other superconductive parameters are highly sensitive to temperature variations at low temperatures, enabling ultra-high temperature resolution (micro-Kelvin scale) and excellent operability in cryogenic environments where conventional thermal scanning microscopy fails
3Object-affected harmful factors
If non-contact thermal measurement is implemented, then sample integrity is maintained, but measurement sensitivity and resolution are reduced
Solution Approach 1:
The patent exploits the phase transition properties of superconductive materials, specifically the sharp changes in electrical and thermal properties that occur at the superconductive critical temperature. By operating near the critical temperature of the superconductive tip, the system achieves extremely high measurement sensitivity through the enhanced response of superconductive parameters to minute temperature changes, maintaining sample integrity while achieving micro-Kelvin temperature resolution
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
The device achieves ultra-sensitive thermal measurements with a temperature resolution of 1 micro-Kelvin and a bandwidth of up to 100MHz, enabling non-invasive thermal imaging with nano-metric spatial resolution while avoiding physical interaction with the sample.
Implementation Method 1
A non-contact thermal measurement device using a superconductive cap with electrically conductive leads that transmit electrical current to determine temperature variations
Implementation Method 2
The device achieves ultra-sensitive thermal measurements with a temperature resolution of 1 micro-Kelvin... determining critical current thereof, the variation in the critical current being indicative of a local temperature of the sample
Data Source
Figure 1~2A
Figure 2B~3
Figure 4A
AI summary
A device and methods for use thereof in low-temperature thermal scanning microscopy, providing non-contact, non-invasive localized temperature and thermal conductivity measurements in nanometer scale ranges with a temperature resolution in the micro-Kelvin order. A superconductive cap mounted on the tip of an elongated support probe is electrically-connected to superconductive leads for carrying electrical current through the cap. The critical superconducting current of the leads is configured to be greater than the critical current supported by the cap, and the cap's critical current is configured to be a function of its temperature. Thus, the temperature of the cap is measured by measuring its critical superconducting current. In a related embodiment, driving a current greater than the critical current of the cap quenches the cap's superconductivity, and permits the cap to dissipate resistive heat into the sample being scanned. Scanning of the sample in this mode thus images its thermal conductivity patterns.