We investigated the coherent evolution of the electronic spin at low temperature in high-quality CHNHPbI polycrystalline films by picosecond-resolved photoinduced Faraday rotation. We show that this coherent evolution can be tuned by choosing the pump-probe energy within the lowest optical-absorption band, and we explain it as the result of two main contributions: the localized electron and the localized hole. Their corresponding amplitude ratios are constant across the lowest absorption band-an observation which disqualifies a free exciton from being at the origin of the electronic spin coherent evolution. We measured a spin coherence time of localized electrons (holes) of 4.4 ns (3.7 ns) at 1.635 eV, which evolves to about 7 ns at 1.612 eV (the hole coherence time remains almost constant at lower energies). Finally, we provide a global image of the spin coherent evolution in bulk metal halide perovskite, which overcomes recent controversies.
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http://dx.doi.org/10.1021/acs.jpclett.1c01790 | DOI Listing |
Behav Brain Sci
January 2025
Department of Anthropology, University of California Los Angeles, San Clemente, CA,
Stibbard-Hawkes's detailed demonstration that in the case of hunter-gatherer artifacts, absence of evidence is not evidence of absence must never be forgotten. The belief that there is a single coherent "human cognitive capacity" difference between modern humans and some unspecified earlier form should be rigorously re-examined.
View Article and Find Full Text PDFJ Psychiatr Res
January 2025
Department of Medicine, Universitat Internacional de Catalunya, Barcelona. c/ Dr. Josep Trueta s/n, Sant Cugat del Vallès, 08195, Barcelona, Spain. Electronic address:
Background: Determining anesthetic depth has been used to assess the optimal timing of electrical stimulus application in electroconvulsive therapy (ECT). This has improved the quality and effectiveness of seizures, as some anesthetics used can decrease efficacy. This study evaluated the influence of the Patient State Index (PSi) on the course of ECT in patients with major depressive disorder (MDD).
View Article and Find Full Text PDFSensors (Basel)
December 2024
Institute of Mechanical Intelligence, Scuola Superiore Sant'Anna, Via G. Moruzzi 1, 56124 Pisa, Italy.
CloudSim is a versatile simulation framework for modeling cloud infrastructure components that supports customizable and extensible application provisioning strategies, allowing for the simulation of cloud services. On the other hand, Distributed Acoustic Sensing (DAS) is a ubiquitous technique used for measuring vibrations over an extended region. Data handling in DAS remains an open issue, as many applications need continuous monitoring of a volume of samples whose storage and processing in real time require high-capacity memory and computing resources.
View Article and Find Full Text PDFAm J Ophthalmol
January 2025
Department of biomedical sciences, Humanitas University, Pieve Emanuele, Milan, Italy.; Ophthalmology Department, Humanitas Gavazzeni, Bergamo, Italy.
Purpose: To investigate the incidence, clinical spectrum and pathophysiology of microcystoid macular edema (MME) in two cohorts of patients with epiretinal membrane (ERM) and idiopathic full thickness macular hole (FTMH).
Design: Single-center, Retrospective, interventional, cohort study.
Methods: Review of clinical charts, structural and en-face optical coherence tomographty (OCT) and fluorescein angiography (FA) imaging of ERM and FTMH eyes which underwent surgery with pars plana vitrectomy and internal limiting membrane (ILM) peel, with a minimum follow-up of 6 months.
Phys Rev Lett
December 2024
State Key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-intense Laser Science, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, 201800, China.
We have observed the Berry phase effect associated with interband coherence in topological surface states (TSSs) using two-color high-harmonic spectroscopy. This Berry phase accumulates along the evolution path of strong field-driven electron-hole quasiparticles in electronic bands with strong spin-orbit coupling. By introducing a secondary weak field, we perturb the evolution of Dirac fermions in TSSs and thus provide access to the Berry phase.
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