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Updated: May 30, 2026
11:33
All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Current driven tri-stable resistance states in magnetic point contacts
I K Yanson1, V V Fisun, Yu G Naidyuk
1B Verkin Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, 47 Lenin Avenue, 61103, Kharkiv, Ukraine.
Summary
Researchers discovered novel tri-stable resistance states in point contacts between metals. These findings in ferromagnetic metal point contacts advance understanding of spin transport phenomena.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Point contacts between normal and ferromagnetic metals are crucial for spintronic devices.
- Understanding spin transport phenomena at interfaces is key to device performance.
Purpose of the Study:
- To investigate the magnetoresistance and transport spectroscopy of point contacts between normal and ferromagnetic metals.
- To explore the origin of novel resistance states observed in these contacts.
Main Methods:
- Utilizing magnetoresistance and transport spectroscopy measurements.
- Employing micromagnetic simulations to model the spin structure.
- Analyzing the behavior of point contact resistance under varying bias current and magnetic fields.
Main Results:
- Observed pronounced hysteresis in point contact resistance.
- Identified bi-stable and novel tri-stable resistance states.
- Interpreted results in terms of surface spin valve and spin vortex states.
Conclusions:
- The modified spin structure at the ferromagnetic interface leads to unique surface spin states.
- These surface spin states, influenced by weakened exchange interaction, dominate spin transfer torque effects at the nanoscale.
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