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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
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Tuning Spin Current Injection at Ferromagnet-Nonmagnet Interfaces by Molecular Design
Angela Wittmann1, Guillaume Schweicher1, Katharina Broch2
1Optoelectronics Group, Cavendish Laboratory, University of Cambridge, J. J. Thompson Avenue, Cambridge CB3 0HE, United Kingdom.
Physical Review Letters
|February 1, 2020
Summary
Researchers explored spin current injection from Permalloy into organic semiconductors. They found that molecular design and interfacial structure significantly tune spin injection efficiency and spin diffusion length in dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) systems.
Area of Science:
- Organic spintronics
- Materials science
- Condensed matter physics
Background:
- Growing interest in organic semiconductors for spintronic applications due to their unique material properties.
- Need to understand and control spin current injection efficiency at interfaces for device performance.
Purpose of the Study:
- To investigate the injection of pure spin current from Permalloy into a dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) small molecule system.
- To systematically study the impact of interfacial properties on spin injection efficiency using molecular design.
Main Methods:
- Utilized ferromagnetic resonance (FMR) to study spin current injection.
- Employed molecular design and side chain substitution of DNTT to tune interfacial properties.
- Analyzed the influence of interfacial molecular structure on spin injection efficiency and spin diffusion length.
Main Results:
- Demonstrated successful spin current injection from Permalloy into the DNTT organic semiconductor.
- Showed that spin injection efficiency at the interface is sensitive to the molecular structure.
- Confirmed that spin diffusion length can be effectively tuned by interfacial molecular design and side chain substitution.
Conclusions:
- Organic semiconductor properties can be tuned through molecular design for spintronic applications.
- Interfacial engineering is crucial for optimizing spin injection efficiency and spin transport in organic spintronics.
- The DNTT system offers a promising platform for developing efficient organic spintronic devices.
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