π-Stacking-Dependent Vibronic Couplings Drive Excited-State Dynamics in Perylenediimide Assemblies

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(25), P. 11386 - 11396

Published: June 14, 2022

Vibronic coupling, the interplay of electronic and nuclear vibrational motion, is considered a critical mechanism in photoinduced reactions such as energy transfer, charge singlet fission. However, our understanding how particular vibronic couplings impact excited-state dynamics lacking due to limited number experimental studies model molecular systems. Herein, we use two-dimensional spectroscopy (2DES) launch interrogate range coherences two distinct types perylenediimide slip stacks─along short long axes, which form either an excimer or mixed state between Frenkel exciton (FE) transfer states. We explore functionality these using quantum beatmaps, display Fourier amplitude signal oscillations function pump probe frequencies, along with knowledge characteristic signatures FE, ionic, species. find that low-frequency mode short-axis stack appears concomitantly formation state, survives 2-fold longer than FE reference monomer, shows phase shift compared other modes. For long-axis stacks, pair modes coupled high-frequency coordinate were found play role mixed-state generation. Our findings thus experimentally reveal complex varying roles tightly packed multimers undergoing processes.

Language: Английский

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Quantum dynamics simulations of the 2D spectroscopy for exciton polaritons

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 159(9)

Published: Sept. 1, 2023

We develop an accurate and numerically efficient non-adiabatic path-integral approach to simulate the non-linear spectroscopy of exciton-polariton systems. This is based on partial linearized density matrix model exciton dynamics with explicit propagation phonon bath environment, combined a stochastic Lindblad cavity loss dynamics. Through simulating both linear polariton two-dimensional electronic spectra, we systematically investigate how light-matter coupling strength rate influence optical response signal. Our results confirm polaron decoupling effect, which reduced exciton-phonon among states due strong interactions. further demonstrate that coherence time can be significantly prolonged compared outside cavity.

Language: Английский

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Higher-Order Multidimensional and Pump–Probe Spectroscopies

The Journal of Physical Chemistry Letters, Journal Year: 2023, Volume and Issue: 14(33), P. 7556 - 7573

Published: Aug. 17, 2023

Transient absorption and coherent two-dimensional spectroscopy are widely established methods for the investigation of ultrafast dynamics in quantum systems. Conventionally, they interpreted framework perturbation theory at third order interaction. Here, we discuss potential higher-(than-third-)order pump–probe multidimensional to provide insight into excited multiparticle states their dynamics. We focus on recent developments from our group. In particular, demonstrate how phase cycling can be used fluorescence-detected isolate higher-order spectra that information about highly such as correlation multiexciton states. coherently detected fifth-order 2D its power track exciton diffusion. Finally, show extract signals even ordinary experiments, providing annihilation-free high excitation densities interactions.

Language: Английский

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A Quantum Algorithm from Response Theory: Digital Quantum Simulation of Two-Dimensional Electronic Spectroscopy

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: 15(5), P. 1484 - 1492

Published: Jan. 31, 2024

Multidimensional optical spectroscopies are powerful techniques to investigate energy transfer pathways in natural and artificial systems. Because of the high information content spectra, numerical simulations response primary importance assist interpretation spectral features. However, increasing complexity investigated systems their quantum dynamics call for development novel simulation strategies. In this work, we consider using digital computers. By combining dynamical nonlinear theory, present a algorithm computing molecular The advantage stems from efficient governed by Hamiltonian, it is demonstrated explicitly considering exciton-vibrational coupling. protocol tested on near-term device, providing linear simple models.

Language: Английский

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Ultrafast laser-assisted perovskite-based optoelectronic devices

Optics & Laser Technology, Journal Year: 2024, Volume and Issue: 176, P. 110877 - 110877

Published: March 30, 2024

Language: Английский

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Observation of Dark States in Two-Dimensional Electronic Spectra of Chlorosomes

The Journal of Physical Chemistry B, Journal Year: 2024, Volume and Issue: 128(15), P. 3575 - 3584

Published: April 3, 2024

Observations of low-lying dark states in several photosynthetic complexes challenge our understanding the mechanisms behind their efficient energy transfer processes. Computational models are necessary for providing novel insights into nature and function states, especially since these not directly accessible spectroscopy experiments. Here, we will focus on signatures dark-type chlorosomes, a light-harvesting complex from green sulfur bacteria well-known uniting broad absorption band with very transfer. In agreement experiments, simulations two-dimensional electronic spectra capture ultrafast exciton occurring 100s femtoseconds within single chlorosome cylinder. The sub-100 fs process corresponds to relaxation single-excitation manifold tube, where all initially created populations bright quickly transferred states. Structural inhomogeneities local scale cause redistribution oscillator strength, leading emergence which dominate presence suppresses loss an isolated via fluorescence quenching, as observed experimentally. Our results further question whether dark-exciton is or merely competes baseplate apparatus bacteria.

Language: Английский

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Mapping electronic decoherence pathways in molecules

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(49)

Published: Nov. 28, 2023

Establishing the fundamental chemical principles that govern molecular electronic quantum decoherence has remained an outstanding challenge. Fundamental questions such as how solvent and intramolecular vibrations or functionalization contribute to remain unanswered are beyond reach of state-of-the-art theoretical experimental approaches. Here we address this challenge by developing a strategy isolate pathways for chromophores immersed in condensed phase environments enables elucidating coherence is lost. For this, first identify resonance Raman spectroscopy general method reconstruct spectral densities with full complexity at room temperature, solvent, fluorescent non-fluorescent molecules. We then show quantitatively capture dynamics from density decomposing overall loss into contributions due individual modes. illustrate utility analyzing DNA base thymine water. Its coherences decay ∼ 30 fs. The early-time determined while solvent. Chemical substitution modulates hydrogen-bond interactions ring water leading fastest decoherence. Increasing temperature leads faster it enhances importance but leaves intact. developed opens key opportunities establish connection between structure needed develop strategies rationally modulate it.

Language: Английский

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A spectrometer design that eliminates incoherent mixing signals in 2D action spectroscopies

The Journal of Chemical Physics, Journal Year: 2024, Volume and Issue: 161(13)

Published: Oct. 3, 2024

Action spectroscopies use a readout created by the action of light on molecules or material rather than optical absorption. Ultrafast 2D photocurrent and fluorescence are two such spectroscopies. Despite their utility, multidimensional suffer from background incoherent population mixing. These backgrounds appear when one molecule impacts that another, creating signal mimics fourth-order response but is really just convolution linear responses. The mixing often much larger desired foreground signals. In this paper, we describe physical mechanisms give rise to signals, drawing Feynman paths for each. There three variations differing pulse ordering. They all have same phase dependence as signals so cannot be removed standard cycling, they do differ in polarization responses dephasing times. We propose, implement, spectrometer design eliminates isotropically oriented samples, leaving only spectra. Our utilizes TWINS interferometer shaper interferometer, each driven with different white-light source pairs within stable, not between two. lack stability interferometers third eliminated scheme ⟨0, π/2, π/4, π/4⟩. also enables both spectra collected simultaneously, thereby enabling direct comparison detection under identical conditions at exact position sample. Using photovoltaic devices made thin films semiconducting carbon nanotubes, demonstrate free background.

Language: Английский

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Formally Exact Simulations of Mesoscale Exciton Diffusion in a Light-Harvesting 2 Antenna Nanoarray

The Journal of Physical Chemistry Letters, Journal Year: 2023, Volume and Issue: 14(12), P. 3077 - 3083

Published: March 22, 2023

The photosynthetic apparatus of plants and bacteria combine atomically precise pigment–protein complexes with dynamic membrane architectures to control energy transfer on the 10–100 nm length scales. Recently, synthetic materials have integrated antenna proteins enhance exciton transport, though influence artificial packing excited-state dynamics in these biohybrid is not fully understood. Here, we use adaptive hierarchy pure states (adHOPS) perform a formally exact simulation excitation within aggregates light-harvesting complex 2 (LH2) range densities. We find that LH2 support remarkable diffusion ranging from 100 at biological density 300 densest previously suggested an aggregate. unprecedented scale calculations also underscores efficiency which adHOPS simulates processes molecular materials.

Language: Английский

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Unifying Nonlinear Response and Incoherent Mixing in Action-2D Electronic Spectroscopy

The Journal of Physical Chemistry Letters, Journal Year: 2023, Volume and Issue: 14(30), P. 6872 - 6879

Published: July 25, 2023

Action-detection has expanded the scope and applicability of 2D electronic spectroscopy, while posing new challenges for unambiguous interpretation spectral features. In this context, identifying origin cross-peaks at early waiting times is not trivial, incoherent mixing often invoked as an unwanted contribution masking nonlinear signal. work, we elaborate on relation between response by analyzing action signal in terms one- two-particle observables. Considering a weakly interacting molecular dimer, show how times, reflecting exciton-exciton annihilation dynamics, can be equivalently interpreted arising from mixing. This equivalence, one hand, highlights information content features related to and, other provides efficient numerical scheme simulate systems.

Language: Английский

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