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Updated: May 8, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Exchange-Coupled Localized States Enable Weak-Field Spin-Polarized Lasing in All-Inorganic CsPbBr3 Microcrystals.
Baihui Nie1,2, Qian Li2,3, Zhengzheng Liu2
1School of Physical Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai 201210, China.
The Journal of Physical Chemistry Letters
|May 7, 2026
Summary
We achieved spin-polarized lasing in manganese-doped perovskite microcrystals by controlling spin dynamics. This breakthrough enables efficient spin-polarized light generation for photonic applications.
Area of Science:
- Materials Science
- Quantum Optics
- Spintronics
Background:
- Spin-polarized lasers are crucial for advanced photonic information processing.
- Lead halide perovskites have shown promise for lasing but suffer from rapid spin relaxation, hindering spin-polarized lasing.
- Developing materials with extended spin lifetimes is essential for practical spin-based photonic devices.
Purpose of the Study:
- To achieve spin-polarized lasing in manganese-doped cesium lead bromide (CsPbBr3) microcrystals.
- To investigate the role of manganese doping and localized states in enhancing spin lifetime.
- To demonstrate weak-field-controlled spin-polarized lasing at room temperature.
Main Methods:
- Fabrication of Mn-doped CsPbBr3 microcrystals.
- Integration of microcrystals with whispering-gallery-mode resonators.
- Spectroscopic measurements under external magnetic fields to analyze carrier dynamics and spin lifetime.
- Characterization of lasing properties, including threshold and degree of circular polarization.
Main Results:
- Mn doping introduced localized states that facilitated ultrafast carrier trapping and back-transfer.
- A significant 5-fold increase in spin lifetime (to 16.6 ps) was observed at a weak magnetic field (300 mT) due to Mn-induced exchange interactions enhancing spin retention.
- Weak-field-controlled spin-polarized lasing was achieved at room temperature with a low threshold (3.05 μJ cm⁻²) and a 39.6% degree of circular polarization.
Conclusions:
- Manganese doping in CsPbBr3 microcrystals effectively enhances spin lifetime by exploiting localized-state dynamics and exchange interactions.
- This work demonstrates a viable pathway for realizing efficient spin-polarized lasing in perovskites at room temperature using weak magnetic fields.
- The findings pave the way for developing novel spintronic and photonic devices based on spin-polarized light emission.
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