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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Dynamic spin polarization by orientation-dependent separation in a ferromagnet-semiconductor hybrid.
V L Korenev1, I A Akimov, S V Zaitsev
1A.F.Ioffe Physical-Technical Institute, Russian Academy of Sciences, 194021 St Petersburg, Russia. korenev@orient.ioffe.ru
Nature Communications
|July 19, 2012
Summary
This study shows a ferromagnetic layer can separate electron spins in a semiconductor quantum well. This enables optical readout of magnetism and control of spin polarization for spintronic devices.
Area of Science:
- Spintronics
- Semiconductor physics
- Materials science
Background:
- Integrating magnetism with semiconductors is key for advanced computing.
- Current ferromagnet/semiconductor hybrids primarily focus on spin injection for readout.
Purpose of the Study:
- To demonstrate a novel hybrid structure for spin manipulation.
- To explore the use of ferromagnetic layers as spin separators.
- To maintain optical properties of semiconductor quantum wells in hybrid devices.
Main Methods:
- Fabrication of a ferromagnet/semiconductor quantum well hybrid structure.
- Utilizing a thin barrier to separate the ferromagnetic layer and quantum well.
- Investigating spin-dependent electron transfer and its effects.
Main Results:
- A Mn-based ferromagnetic layer effectively separates carrier spins in the quantum well.
- Accumulation of non-equilibrium electron-spin polarization via spin-dependent transfer.
- Preservation of the quantum well's excellent optical properties.
Conclusions:
- The hybrid design enables orientation-dependent spin separation.
- Optical readout of ferromagnetism and control of spin polarization are feasible.
- This approach advances the development of all-in-one-chip spintronic devices.
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