Experimentelle Physik 2, Technische Universität Dortmund, 44227, Dortmund, Germany.
Ioffe Institute, Russian Academy of Sciences, 194021, St. Petersburg, Russia.
Nat Commun. 2023 Feb 8;14(1):699. doi: 10.1038/s41467-023-36165-0.
The spin physics of perovskite nanocrystals with confined electrons or holes is attracting increasing attention, both for fundamental studies and spintronic applications. Here, stable [Formula: see text] lead halide perovskite nanocrystals embedded in a fluorophosphate glass matrix are studied by time-resolved optical spectroscopy to unravel the coherent spin dynamics of holes and their interaction with nuclear spins of the Pb isotope. We demonstrate the spin mode locking effect provided by the synchronization of the Larmor precession of single hole spins in each nanocrystal in the ensemble that are excited periodically by a laser in an external magnetic field. The mode locking is enhanced by nuclei-induced frequency focusing. An ensemble spin dephasing time [Formula: see text] of a nanosecond and a single hole spin coherence time of T = 13 ns are measured. The developed theoretical model accounting for the mode locking and nuclear focusing for randomly oriented nanocrystals with perovskite band structure describes the experimental data very well.
具有受限电子或空穴的钙钛矿纳米晶体的自旋物理特性引起了越来越多的关注，无论是对于基础研究还是自旋电子学应用来说都是如此。在这里，我们通过时间分辨光光谱法研究了嵌入在氟磷酸盐玻璃基质中的稳定[Formula: see text]卤化铅钙钛矿纳米晶体，以揭示空穴的相干自旋动力学及其与 Pb 同位素核自旋的相互作用。我们证明了通过在外部磁场中周期性地用激光激发每个纳米晶体中单个空穴自旋的拉莫尔进动的同步来提供自旋模式锁定效应。模式锁定通过核诱导的频率聚焦得到增强。测量得到的纳米晶集体自旋退相时间[Formula: see text]为纳秒量级，单个空穴自旋相干时间 T=13 ns。该理论模型很好地描述了实验数据，该模型考虑了具有钙钛矿能带结构的随机取向纳米晶体的模式锁定和核聚焦。
