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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
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Arc hopping dynamics induced by interfacial negative differential resistance.
Jindong Huo1, Alex Rontey2, Yifei Wang1
1Electrical Insulation Research Center, Institute of Materials Science, University of Connecticut, Storrs, CT 06269, USA.
PNAS Nexus
|February 6, 2023
Summary
Negative differential resistance (NDR) in plasma sheaths drives pattern formation in plasma-solid interactions. This discovery explains arc hopping dynamics and offers new ways to control plasma surface treatments.
Area of Science:
- Plasma Physics
- Surface Science
- Nonlinear Dynamics
Background:
- Pattern formation in plasma-solid interactions is crucial for applications like plasma etching and surface treatment.
- Arc attachments constrict into self-organized spots, posing a research challenge.
Purpose of the Study:
- To investigate the mechanism behind pattern formation in gliding arc discharges.
- To understand the hopping dynamics of plasma attachments on surfaces.
Main Methods:
- Analysis of gliding arc discharge dynamics in a Jacob's Ladder setup.
- Instability phase-diagram analysis.
- Comprehensive magnetohydrodynamics (MHD) computation.
Main Results:
- Identified negative differential resistance (NDR) across the plasma sheath as the cause of hopping patterns.
- Demonstrated that NDR leads to activator-inhibitor dynamics governing current density redistribution and spot formation.
- MHD simulations successfully reproduced experimental arc hopping phenomena.
Conclusions:
- Sheath NDR plays an essential role in plasma-solid surface pattern formation.
- This finding opens new avenues for research in manipulating plasma-solid interactions.
- The study explains spontaneous arc attachment constriction in the NDR regime.
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