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Title: Observation of long spin lifetime in MAPbBr 3 single crystals at room temperature
Abstract The emergence of hybrid metal halides (HMH) materials, such as the archetypal CH3NH3PbBr3, provides an appealing material platform for solution-processed spintronic applications due to properties such as unprecedented large Rashba spin-splitting states and highly efficient spin-to-charge (StC) conversion efficiencies. Here we report the first study of StC conversion and spin relaxation time in MAPbBr3single crystals at room temperature using a spin pumping approach. Microwave frequency and power dependence of StC responses are both consistent with the spin pumping model, from which an inverse Rashba–Edelstein effect coherence length of up to ∼30 picometer is obtained, highlighting a good StC conversion efficiency. The magnetic field angular dependence of StC is investigated and can be well-explained by the spin precession model under oblique magnetic field. A long spin relaxation time of up to ∼190 picoseconds is obtained, which can be attributed to the surface Rashba state formed at the MAPbBr3interface. Our oblique Hanle effect by FMR-driven spin pumping technique provides a reliable and sensitive tool for measuring the spin relaxation time in various solution processed HMH single crystals.  more » « less
Award ID(s):
1933297
PAR ID:
10303220
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Physics: Materials
Volume:
3
Issue:
1
ISSN:
2515-7639
Page Range / eLocation ID:
Article No. 015012
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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