Mode locking of hole spin coherences in CsPb(Cl,Br)${}_3$ perovskite nanocrystals

Abstract

The spin physics of perovskite nanocrystals with confined electrons or holes is attracting increasing attention, both for fundamental studies and spintronic applications. Here, stable CsPb(Cl${}_{0.5}$Br${}_{0.5}$)${}_3$ 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 ${}^{207}$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 $T_2^{\ast }$ of a nanosecond and a single hole spin coherence time of $T_2=13$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.

arXiv commentMain paper of 9 pages and 3 figures. Supplementary material of 16 pages and 12 figures

References in corpus (12)

• Bright triplet excitons in lead halide perovskites
• Ultrafast optical rotations of electron spins in quantum dots
• Coherent spin dynamics of electrons and holes in CsPbBr${}_3$ perovskite crystals
• Pump-Probe Faraday Rotation and Ellipticity in an Ensemble of Singly Charged Quantum Dots
• The Landé factors of electrons and holes in lead halide perovskites: universal dependence on the band gap
• Optical orientation and alignment of excitons in ensembles of inorganic perovskite nanocrystals
• Coherent Spin Precession and Lifetime-Limited Spin Dephasing in CsPbBr3 Perovskite Nanocrystals
• Coherent spin dynamics of electrons and holes in semiconductor quantum wells and quantum dots under periodical optical excitation: resonant spin amplification versus spin mode-locking
• Spin polarization recovery and Hanle effect for charge carriers interacting with nuclear spins in semiconductors
• Suppression of nuclear spin fluctuations in an InGaAs quantum dot ensemble by GHz-pulsed optical excitation
• Dynamics of nuclear spin polarization induced and detected by coherently precessing electron spins in fluorine-doped ZnSe
• Shielding of external magnetic field by dynamic nuclear polarization in (In,Ga)As quantum dots

Cited by in corpus (5)

• Tailoring the electron and hole Landé factors in lead halide perovskite nanocrystals by quantum confinement and halide exchange
• Giant optical orientation of exciton spins in lead halide perovskite crystals
• Coherent Spin Dynamics of Electrons in Two-Dimensional (PEA)${}_2$PbI${}_4$ Perovskites
• Hole spin coherence in InAs/InAlGaAs self-assembled quantum dots emitting at telecom wavelengths
• Perovskite Nanocrystals as Emerging Single-Photon Emitters: Progress, Challenges, and Opportunities