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Local noise in a diffusive conductor
E S Tikhonov1,2, D V Shovkun1,2, D Ercolani3
1Moscow Institute of Physics and Technology, Dolgoprudny, 141700, Russia.
Scientific Reports
|July 29, 2016
Summary
Researchers developed a miniature noise probe to measure local noise temperature in current-biased conductors. This overcomes current conservation limitations, enabling non-invasive measurements in non-equilibrium electronic systems.
Area of Science:
- Condensed Matter Physics
- Nanoscale Science
- Quantum Electronics
Background:
- Local control and measurement of non-equilibrium states are crucial for energy harvesting, thermoelectrics, and nano-electronic heat management.
- Existing local probes include tunnel junctions and Raman thermography, but measuring noise locally is constrained by current conservation.
Purpose of the Study:
- To demonstrate a method for measuring the local noise temperature of a current-biased diffusive conductor.
- To overcome the fundamental constraint of current conservation that typically makes noise a property of the entire conductor.
Main Methods:
- Utilized a miniature noise probe to interact with a current-biased diffusive conductor.
- Developed an approach to circumvent the limitations imposed by current conservation.
Main Results:
- Successfully measured the local noise temperature of the conductor.
- The developed method is virtually non-invasive to electronic energy distributions.
Conclusions:
- The miniature noise probe effectively measures local noise temperature in non-equilibrium regimes.
- This technique extends local measurement capabilities into strongly non-equilibrium electronic systems.
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