The development of the photostable higher‐order multiphoton‐excited (MPE) upconversion single microcrystalline material is fundamentally and technologically important, but very challenging. Here, up to five‐photon excited luminescence in a host–guest metal–organic framework (MOF) and perovskite quantum dot (QD) hybrid single crystal ZJU‐28⊃MAPbBr3is shown via an in situ growth approach. Such a MOF strategy not only results in a high QD loading concentration, but also significantly diminishes the aggregation‐caused quenching (ACQ) effect, provides effective surface passivation, and greatly reduces the contact of the QDs with the external bad atmosphere due to the confinement effect and protection of the framework. These advantages make the resulting ZJU‐28⊃MAPbBr3single crystals possess high PLQY of ≈51.1%, a high multiphoton action cross‐sections that can rival the current highest record (measured in toluene solution), and excellent photostability. These findings liberate the excellent luminescence and nonlinear optical properties of perovskite QDs from the solution system to the solid single‐crystal system, which provide a new avenue for the exploitation of high‐performance multiphoton excited hybrid single microcrystal for future optoelectronic and micro–nano photonic integration applications.
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
- NSF-PAR ID:
- 10303220
- 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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