Revealing a full quantum ladder by nonlinear spectroscopy

Coherent two-dimensional spectroscopy in the IR or the visible region is very effective for studying correlations, energy relaxation/transfer pathways in complex multi-chromophore or multi-mode systems. However, it is usually restricted up to two-quanta excitations and their properties. In this paper, an arbitrary level of excitation is suggested as the utility to scan nonlinear potential surfaces of quantum systems up to a desired excitation degree. This can be achieved by a simple three-pulse laser spectroscopy approach. Accurate evaluation of high-level anharmonicities as well as transition amplitudes can be directly obtained. Additionally, questions regarding the quantum nature of the probed system can be addressed by studying absolute peak positions.

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Global accurate diabatic potential surfaces for the reaction H + Li2

RSC Advances ◽

10.1039/d0ra05777k ◽

2020 ◽

Vol 10 (64) ◽

pp. 39226-39240

Author(s):

Ruilin Yin ◽

Nan Gao ◽

Jing Cao ◽

Yanchun Li ◽

Dequan Wang ◽

...

Keyword(s):

Ab Initio ◽

Adiabatic Potential ◽

Basis Set ◽

Potential Surfaces ◽

High Level

The adiabatic potential energies for the lowest three states of a Li2H system are calculated with a high level ab initio method (MCSCF/MRCI) with a large basis set.

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Erratum: Nonlinear spectroscopy of controllable many-body quantum systems (2014 New J. Phys. 16 092001)

New Journal of Physics ◽

10.1088/1367-2630/17/1/019601 ◽

2015 ◽

Vol 17 (1) ◽

pp. 019601

Author(s):

Manuel Gessner ◽

Frank Schlawin ◽

Hartmut Häffner ◽

Shaul Mukamel ◽

Andreas Buchleitner

Keyword(s):

Quantum Systems ◽

Nonlinear Spectroscopy ◽

Many Body

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Critically Assessing the Application of Quantum Corrections to Classical Thermal Conductivity Predictions

Volume 2: Theory and Fundamental Research; Aerospace Heat Transfer; Gas Turbine Heat Transfer; Computational Heat Transfer ◽

10.1115/ht2009-88129 ◽

2009 ◽

Author(s):

J. E. Turney ◽

A. J. H. McGaughey ◽

C. H. Amon

Keyword(s):

Thermal Conductivity ◽

Lattice Dynamics ◽

Md Simulation ◽

Ad Hoc ◽

Quantum Systems ◽

Quantum Corrections ◽

Quantum Mechanical Treatment ◽

Anharmonic Lattice ◽

Total Energies ◽

Full Quantum

Quantum corrections can be used to map the thermal conductivity predicted in a classical framework [e.g., a molecular dynamics (MD) simulation] to a corresponding value in a quantum system. This procedure is accomplished by equating the total energies and energy fluxes of the classical and quantum systems. The validity of these corrections is questionable because they are introduced in an ad hoc manner and are not derived from first principles. In this work, the validity of these quantum corrections is examined by comparing the thermal conductivity of Stillinger-Weber silicon calculated using a full quantum mechanical treatment to a quantum-corrected value predicted from a classical framework between temperatures of 10 K and 1000 K. The quantum and classical predictions are obtained using anharmonic lattice dynamics calculations. We find discrepancies between the quantum-corrected predictions and the quantum predictions obtained directly. We investigate the causes of these discrepancies and from our findings, conclude that quantum thermal conductivities cannot be predicted by applying simple corrections to the values obtained from a purely classical framework.

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Lifetime dynamics of plasmons in the few-atom limit

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1805357115 ◽

2018 ◽

Vol 115 (37) ◽

pp. 9134-9139 ◽

Cited By ~ 12

Author(s):

Kyle D. Chapkin ◽

Luca Bursi ◽

Grant J. Stec ◽

Adam Lauchner ◽

Nathaniel J. Hogan ◽

...

Keyword(s):

Vibrational Relaxation ◽

Visible Region ◽

Electron Excitation ◽

Quantum Systems ◽

Single Electron ◽

Quantum Limit ◽

Excited State Lifetime ◽

Electron Hole ◽

Rapid Decay ◽

Polycyclic Aromatic

Polycyclic aromatic hydrocarbon (PAH) molecules are essentially graphene in the subnanometer limit, typically consisting of 50 or fewer atoms. With the addition or removal of a single electron, these molecules can support molecular plasmon (collective) resonances in the visible region of the spectrum. Here, we probe the plasmon dynamics in these quantum systems by measuring the excited-state lifetime of three negatively charged PAH molecules: anthanthrene, benzo[ghi]perylene, and perylene. In contrast to the molecules in their neutral state, these three systems exhibit far more rapid decay dynamics due to the deexcitation of multiple electron–hole pairs through molecular plasmon “dephasing” and vibrational relaxation. This study provides a look into the distinction between collective and single-electron excitation dynamics in the purely quantum limit and introduces a conceptual framework with which to visualize molecular plasmon decay.

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The theoretical investigation of the opto-electronic properties of designed molecules having 2-(2-Methylene-3-oxo-indane-1-ylidene)malononitrile as end-capped acceptors

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2019-1523 ◽

2020 ◽

Vol 235 (6) ◽

pp. 785-804

Author(s):

Amina Tariq ◽

Hina Ramzan ◽

Syed Waqas Ahmad ◽

Ijaz Ahmad Bhatti ◽

Maryam Ajmal ◽

...

Keyword(s):

Electronic Properties ◽

Density Functional ◽

Visible Region ◽

Potential Surfaces ◽

Functional Theory ◽

Photovoltaic Application ◽

High Ionization ◽

Donor Acceptor ◽

Electron Transportation ◽

Reorganization Energies

Abstract Five acceptor-donor-acceptor molecules having different core units with 2-(2-Methylene-3-oxo-indane-1-ylidene)malononitrile as end capped terminal acceptor unit were designed. The ground state geometries and electronic properties were calculated by using density functional theory (DFT) at MPW1PW91/6-31G(d,p) level of theory. The absorption spectra were computed by using time dependent DFT at MPW1PW91/6-31G(d,p) level of theory. The designed molecules have broad absorption range in visible region. M3 shows relatively lower band gap so that having high light harvesting efficiency (LHE). The molecules consider as better hole blocking materials in term of high ionization potentials. The reorganization energies calculation of M1, M2 and M4 manifests that these molecules are the optimal candidate for electron transportation. High value of Voc has been observed for molecules which would favorably contribute in power conversion efficiency. M1, M2, M4 and M5 are more stable in terms of absolute hardness and electrostatic potential surfaces. All molecules show good opto-electronic properties in the aspect of their use in photovoltaic application.

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8. Three-Level Atoms: Applications to Nonlinear Spectroscopy—Open Quantum Systems

Principles of Laser Spectroscopy and Quantum Optics ◽

10.1515/9781400837045-009 ◽

2011 ◽

pp. 159-183

Keyword(s):

Open Quantum Systems ◽

Quantum Systems ◽

Nonlinear Spectroscopy ◽

Open Quantum

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A SYNTHESIS OF INVARIANT STRUCTURES WITH MEMORY IN TWO-DIMENSIONAL SPACE

International Journal of Modern Physics C ◽

10.1142/s0129183100000766 ◽

2000 ◽

Vol 11 (05) ◽

pp. 853-864 ◽

Cited By ~ 3

Author(s):

ALEXANDER YUDASHKIN

Keyword(s):

Potential Function ◽

Dimensional Space ◽

Nonlinear Dynamical System ◽

Dimensional Euclidean Space ◽

Two Dimensional ◽

Nonlinear Dynamical ◽

Self Assembling ◽

Nonlinear Potential ◽

The Stability ◽

High Level

A problem of self-organized structure storage and retrieving is considered. The novel model of nonlinear dynamical system for multi-unit structures memorizing is proposed and its properties are investigated in this paper. The multi-unit system consists of N points in the two-dimensional Euclidean space, and its dynamics is defined by a potential function, that is translation and rotation invariant relatively points coordinates. The nonlinear potential function allows to compose attractors corresponding to the proper configurations of points, while these configurations are memorized by the system. Any initial form flows to one of the attractors independently from possible rotations and spatial shifts. The system can memorize and successfully restore up to N-2 required configurations. The characteristics of structure retrieving in the presence of beginning form distortion are considered, and the stability of method is shown even in the case of high level noise. The proposed approach could be helpful to design physical, technical and informational objects with the desired self-assembling properties.

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EXCEPTIONAL POINTS IN OPEN AND PT-SYMMETRIC SYSTEMS

Acta Polytechnica ◽

10.14311/ap.2014.54.0106 ◽

2014 ◽

Vol 54 (2) ◽

pp. 106-112 ◽

Cited By ~ 12

Author(s):

Hichem Eleuch ◽

Ingrid Rotter

Keyword(s):

Open Quantum Systems ◽

Level Density ◽

Quantum Systems ◽

Point Of View ◽

Eigenvalues And Eigenfunctions ◽

Open Quantum ◽

Exceptional Points ◽

Characteristic Features ◽

High Level ◽

Symmetric Systems

Exceptional points (EPs) determine the dynamics of open quantum systems and cause also PT symmetry breaking in PT symmetric systems. From a mathematical point of view, this is caused by the fact that the phases of the wavefunctions (eigenfunctions of a non-Hermitian Hamiltonian) relative to one another are not rigid when an EP is approached. The system is therefore able to align with the environment to which it is coupled and, consequently, rigorous changes of the system properties may occur. We compare analytically as well as numerically the eigenvalues and eigenfunctions of a 2 × 2 matrix that is characteristic either of open quantum systems at high level density or of PT symmetric optical lattices. In both cases, the results show clearly the influence of the environment on the system in the neighborhood of EPs. Although the systems are very different from one another, the eigenvalues and eigenfunctions indicate the same characteristic features.

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