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Updated: May 8, 2025
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Resonant Spin Amplification and Accumulation in MAPbI3 Single Crystals.
Erik Kirstein1, Dmitri R Yakovlev1, Evgeny A Zhukov1
1Technische Universität Dortmund, Experimentelle Physik 2, 44227, Dortmund, Germany.
Summary
Lead halide perovskites exhibit long-lived spin polarization, crucial for quantum technologies. Researchers observed spin dynamics in methylammonium lead iodide, revealing potential for spintronic applications.
Area of Science:
- Quantum physics and materials science
- Semiconductor spintronics
Background:
- Quantum technologies and spintronics demand materials with stable, optically controllable spin polarization.
- Lead halide perovskites possess unique band structures and spin-dependent properties making them promising candidates.
Purpose of the Study:
- To investigate carrier spin dynamics in methylammonium lead iodide (MAPbI3) single crystals.
- To assess the suitability of MAPbI3 for quantum technological applications based on spin phenomena.
Main Methods:
- Time-resolved Kerr ellipticity technique at cryogenic temperatures.
- Exploitation of spin accumulation effects using resonant spin amplification, polarization recovery, and spin inertia.
Main Results:
- Observed long longitudinal electron spin relaxation times (T1 = 30 ns).
- Measured long transverse electron spin dephasing times (T2*).
- Demonstrated spin dynamics exceeding the laser pulse repetition period, leading to spin accumulation.
Conclusions:
- Lead halide perovskites are a viable platform for quantum technologies leveraging spin-dependent phenomena.
- The observed spin dynamics and accumulation effects in MAPbI3 are significant for spintronic device development.
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