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Rashba-Related Spin-Selective Effect in 2D Chiral Perovskites with Achiral Organic Cation Spacers
Junzi Li1,2, Xing Liu1, Guodan Wei1
1Macao Centre for Research and Development in Advanced Materials, Institute of Applied Physics and Materials Engineering, University of Macau, Taipa, Macao S.A.R.999078, China.
Nano Letters
|July 2, 2026
Summary
Alloying achiral and chiral spacers in 2D chiral perovskites enhances spin-selective light interactions. This method tunes Rashba-related effects for improved spin-optoelectronic device performance.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Optoelectronics
Background:
- Two-dimensional (2D) chiral perovskites are explored for magnetic-field-free spin-selective light-matter interactions.
- The role of organic cations in modulating Rashba-related spin effects remains unclear.
Purpose of the Study:
- To investigate the impact of alloying achiral and chiral spacers on spin-selective phenomena in 2D chiral perovskites.
- To understand how organic cation modification influences chiroptical activity and spin-dependent optical responses.
Main Methods:
- Density Functional Theory (DFT) calculations.
- Femtosecond circularly polarized transient absorption spectroscopy.
- Fabrication and characterization of mixed-spacer 2D chiral perovskite films.
Main Results:
- Mixed-spacer films (achiral n-butylammonium in chiral methylbenzylammonium lattice) show enhanced chiroptical activity and spin-dependent optical responses.
- Spacer alloying perturbs local structure, modifying Rashba-related band-edge asymmetry.
- Achieved larger spin-selective transient response asymmetry and enhanced optical Stark effect.
Conclusions:
- Achiral-chiral spacer alloying is an effective strategy to tune spin-selective phenomena in 2D chiral perovskites.
- This approach enables regulation of Rashba-related spin effects for coherent spin-optoelectronic functioning.
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