The coherent spin dynamics of holes are investigated for CsPbBr$_3$ and CsPb(Cl,Br)$_3$ perovskite nanocrystals in a glass matrix using the time-resolved Faraday rotation/ellipticity techniques. In an external magnetic field, pronounced Larmor spin precession of the hole spins is detected across a wide temperature range from 5 to 300 K. The hole Landé $g$-factor varies in the range of $0.8-1.5$, in which it increases with increasing high energy shift of the exciton due to enhanced confinement in small nanocrystals. The hole spin dephasing time decreases from 1 ns to 50 ps in this temperature range. Nuclear spin fluctuations have a pronounced impact on the hole spin dynamics. The hyperfine interaction of the holes with nuclear spins modifies their spin polarization decay and induces their spin precession in zero external magnetic field. The results can be well described by the model developed in Ref. 41, from which the hyperfine interaction energy of a hole spin with the nuclear spin fluctuation in range of $2-5$ $μ$eV is evaluated.
Millisecond-long electron spin lifetime in CsPbI$_3$ perovskite nanocrystals revealed by optically detected magnetic resonance
Technische Universität Dortmund（多特蒙德工业大学）；Ioffe Institute, Russian Academy of Sciences（俄罗斯科学院伊俄费研究所）；P.N. Lebedev Physical Institute of the Russian Academy of Sciences（俄罗斯科学院列别捷夫物理研究所）；Spin Optics Laboratory, St. Petersburg State University（圣彼得堡大学旋光实验室）；ITMO University（ITMO大学）；St. Petersburg State Institute of Technology（圣彼得堡国立理工学院）
Hyperfine versus exchange interaction in the spin dynamics of spatially indirect excitons in CsPbI$_{3}$ perovskite nanocrystals
Rzhanov Institute of Semiconductor Physics, Siberian Branch of the Russian Academy of Sciences（俄罗斯科学院西伯利亚分院热瓦诺夫半导体物理研究所）；Technische Universität Dortmund（多特蒙德工业大学）；Ioffe Institute, Russian Academy of Sciences（俄罗斯科学院伊俄费研究所）；Spin Optics Laboratory, St. Petersburg State University（圣彼得堡大学旋光实验室）；ITMO University（ITMO大学）；St. Petersburg State Institute of Technology（圣彼得堡国立技术学院）
Nonlinear optical responses of all-inorganic lead halide perovskite nanostructures by time-resolved beam-deflection technique
我们研究了非线性折射在全无机卤化物钙钛矿，CsPbBr $_3$和CsPbBr $_{1.5}$ I $_{1.5}$纳米片和量子点胶体在甲苯中，通过一种新的光束偏转技术，使用近共振连续波激光。本文所测量的非线性折射及其随时间的演化是由热透镜效应引起的。热输运的强度依赖的热扩散速率的非线性行为已被观察到。在高强度下测量了对流热流的影响。与相应的纳米片样品相比，量子点具有更高的非线性折射，这可能是由于降低的维度。非线性折射率的有效值，估计在这里的近共振激发，超过那些在文献中报道的有机-无机混合钙钛矿在非共振激发制度，由几个数量级。
