circular polarization  (Nikon)

Journal: Nature Communications

Article Title: Precision engineering chiral interfaces for efficient spin injection in metal halide heterostructures

doi: 10.1038/s41467-026-69455-4

Figure Lengend Snippet: a Schematics of the charge transfer process under circularly polarized light in PbI 2 . The right-circularly polarized excitation ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\sigma }^{+}$$\end{document} σ + ) with an angular momentum of +1 promotes the transfer of spin-up electrons from the valence band to the conduction band. The spin relaxation causes the spin-flip in the conduction band. Decay kinetics are probed at 500 nm in circularly polarized TA spectra of b CHS-Ⅰ and c CHS-Ⅱ, showing the difference between co-circular ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\sigma }^{+}{\sigma }^{+}$$\end{document} σ + σ + , red circles) and cross-circular ( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\sigma }^{+}{\sigma }^{-}$$\end{document} σ + σ − , blue circles) pump-probe configurations. Green circles represent the signal of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\Delta A}_{{\sigma }^{+}{{\rm{\sigma }}}^{-}}-{\Delta A}_{{\sigma }^{+}{{\rm{\sigma }}}^{+}}$$\end{document} Δ A σ + σ − − Δ A σ + σ + . Circularly polarized TA spectra were collected under 365 nm \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\sigma }^{+}$$\end{document} σ + excitation with a pump fluence of 6 μJ/cm 2 . The solid curves are obtained by fitting the data to a mono-exponential decay function to determine the exciton lifetimes of CHS-Ⅰ and CHS-Ⅱ. d Schematics of spin polarization achieved by spin-polarized charge transfer under linearly polarized light in the heterostructures. Spin-up electrons transfer from PbI 2 to R -NEAPbI 3 due to a type-Ⅱ heterojunction, and holes transfer from the other direction. TA kinetics of e CHS-Ⅰ and f CHS-Ⅱ with linear pump and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\sigma }^{+}$$\end{document} σ + or \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\sigma }^{-}$$\end{document} σ − probes at 500 nm showing net spin polarization. The CTA polarization is calculated by( \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\Delta A}_{{{\rm{\sigma }}}^{+}}-{\Delta A}_{{{\rm{\sigma }}}^{-}}$$\end{document} Δ A σ + − Δ A σ − )/ \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$({\Delta A}_{{{\rm{\sigma }}}^{+}}+{\Delta A}_{{{\rm{\sigma }}}^{-}})\times 100\%$$\end{document} ( Δ A σ + + Δ A σ − ) × 100 % . TA spectra were collected under 465 nm linearly polarized light with a pump fluence of 6 μJ/cm 2 .

Article Snippet: The circular polarization characteristics were confirmed by polarimeters (Thorlabs).

Techniques: