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Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
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Kinetically Controlled Structural Transitions in Layered Halide-Based Perovskites: An Approach to Modulate Spin
Yi Xie1,2, Ruyi Song3, Akash Singh1,2
1Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.
Journal of the American Chemical Society
|August 11, 2022
Summary
Researchers demonstrate kinetic control over spin splitting in hybrid organic-inorganic perovskites (HOIPs) by manipulating temperature-induced structural transitions. This offers a new pathway for spintronic applications by modulating electronic properties through controlled cooling rates.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid-State Chemistry
Background:
- Two-dimensional hybrid organic-inorganic perovskites (HOIPs) show promise for spintronics due to spin splitting.
- Achieving significant spin splitting and controlling inversion symmetry breaking in HOIPs remains challenging.
- Existing methods for controlling symmetry breaking in HOIPs are limited.
Purpose of the Study:
- To investigate the modulation of structural and electronic properties in HOIPs through temperature-induced structural transitions.
- To explore the role of cooling rate in controlling inversion symmetry breaking and chirality transfer.
- To demonstrate a method for tuning spin splitting in HOIPs for spintronic applications.
Main Methods:
- Utilized (S-2-MeBA)2PbI4 as a model system for studying temperature-induced structural transitions.
- Employed ultrafast calorimetry to determine structural relaxation times.
- Applied density functional theory (DFT) calculations to analyze electronic band structure and spin splitting.
Main Results:
- A temperature-induced structural transition at ~180 K was observed in (S-2-MeBA)2PbI4, altering inversion symmetry breaking.
- Cooling rate dictates the occurrence of the structural transition: slow cooling induces it, while rapid quenching inhibits it.
- The low-temperature phase exhibits more significant spin splitting than the room-temperature phase, confirmed by DFT.
- Kinetic control over phase transitions allows switching between distinct states with varying structural distortions.
Conclusions:
- Kinetic control of crystal-to-crystal transitions via thermal cycling can effectively modulate spin splitting in HOIPs.
- This approach provides a novel pathway for developing spintronic devices.
- Sluggish phase transitions in HOIPs can be exploited for switching and controlling physical phenomena reliant on structural distortions and lattice symmetry.
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