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.

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpclett.1c01790DOI Listing

Publication Analysis

Top Keywords

coherent evolution
20
electronic spin
12
spin coherent
12
coherence time
8
spin
5
coherent
5
evolution
5
energy tuning
4
tuning electronic
4
evolution methylammonium
4

Similar Publications

What would be pre-modern human cognition?

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 PDF

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 PDF

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 PDF

Microcystoid macular edema in epiretinal membrane: not a retrograde maculopathy.

Am 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.

View Article and Find Full Text PDF

Probing Berry Phase Effect in Topological Surface States.

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.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!