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Nuclear Berry curvature effects emerge from electronic spin degeneracy and canlead to non-trivial spin-dependent (nonadiabatic) nuclear dynamics. However, such effects are completely neglected in all current mixed quantum-classical methods…

Chemical Physics · Physics 2022-08-29 Xuezhi Bian , Yanze Wu , Jonathan Rawlinson , Robert G. Littlejohn , Joseph E. Subotnik

We address the issues of decoherence, frustrated hops and internal consistency in surface hopping. We demonstrate that moving away from an independent-trajectory picture is the strategy which allows us to propose a robust surface hopping…

Chemical Physics · Physics 2025-09-01 Lea M. Ibele , Eduarda Sangiogo Gil , Peter Schürger , Rodrigue Noc , Federica Agostini

We theoretically study the dynamics of an adiabatic sweep through a Feshbach resonance, thereby converting a degenerate quantum gas of fermionic atoms into a degenerate quantum gas of bosonic dimers. Our analysis relies on a zero…

Other Condensed Matter · Physics 2009-11-11 I. Tikhonenkov , E. Pazy , Y. B. Band , M. Fleischhauer , A. Vardi

Fr\'echet means on non-Euclidean spaces may exhibit nonstandard asymptotic rates rendering quantile-based asymptotic inference inapplicable. We show here that this affects, among others, all circular distributions whose support exceeds a…

Methodology · Statistics 2021-07-28 Shayan Hundrieser , Benjamin Eltzner , Stephan F. Huckemann

Finite Sample Smeariness (FSS) has been recently discovered. It means that the distribution of sample Fr\'echet means of underlying rather unsuspicious random variables can behave as if it were smeary for quite large regimes of finite…

Statistics Theory · Mathematics 2021-03-02 Benjamin Eltzner , Shayan Hundrieser , Stephan F. Huckemann

The possibility to apply phase-space methods to many-body interacting systems might provide accurate descriptions of correlations with a reduced numerical cost. For instance, the so--called stochastic mean-field phase-space approach, where…

Nuclear Theory · Physics 2020-04-22 Thomas Czuba , Denis Lacroix , David Regnier , Ibrahim Ulgen , Bulent Yilmaz

We carried out extensive studies to examine the performance of the fewest-switches surface hopping method in the description of the ultrafast intersystem crossing dynamic of various singlet-triplet (S-T) models by comparison with the…

Chemical Physics · Physics 2019-05-22 Jiawei Peng , Yu Xie , Deping Hu , Zhenggang Lan

Quantum coherence of open quantum systems is usually compromised because of the interaction with the ambient environment. A "decoherence-free subspace" (DFS) of the system Hilbert space is defined where the evolution remains unitary. In the…

Quantum Physics · Physics 2010-02-12 E. Jonckheere , A. Shabani , A. T. Rezakhani

A procedure based on a Mixture Density Model for correcting experimental data for distortions due to finite resolution and limited detector acceptance is presented. Addressing the case that the solution is known to be non-negative, in the…

Data Analysis, Statistics and Probability · Physics 2015-03-09 Nikolai Gagunashvili

The generalized density matrix (GDM) method is used to calculate microscopically the parameters of the collective Hamiltonian. Higher order anharmonicities are obtained consistently with the lowest order results, the mean field…

Nuclear Theory · Physics 2011-09-23 L. Y. Jia

Currently, there is a growing interest in the development of a new hierarchy of methods based on the concept of seniority, which has been introduced quite recently in quantum chemistry. Despite the enormous potential of these methods, the…

Chemical Physics · Physics 2022-12-07 Bruno Senjean , Saad Yalouz , Naoki Nakatani , Emmanuel Fromager

The surface code, one of the leading candidates for quantum error correction, is known to protect encoded quantum information against stochastic, i.e., incoherent errors. The protection against coherent errors, such as from unwanted gate…

Quantum Physics · Physics 2025-10-28 Jan Behrends , Benjamin Béri

We revisit a recent proposal to model nonadiabatic problems with a complex-valued Hamiltonian through a phase-space surface hopping (PSSH) algorithm employing a pseudo-diabatic basis. Here, we show that such a pseudo-diabatic PSSH (PD-PSSH)…

Quantum Physics · Physics 2023-01-25 Yanze Wu , Joseph Subotnik

To quantify the effect of decoherence in quantum measurements, it is desirable to measure not merely the square modulus of the spatial wavefunction, but the entire density matrix, whose phases carry information about momentum and how pure…

Quantum Physics · Physics 2009-10-30 Max Tegmark

The standard smoothed particle hydrodynamics (SPH) method suffers from tensile instability, resulting in particle clumping and void regions under negative pressure conditions. In this study, we extend the transport-velocity formulation of…

Fluid Dynamics · Physics 2024-11-22 Zhentong Wang , Oskar J. Haidn , Xiangyu Hu

Conservation laws in a quantum many-body system play a direct role in its dynamic behavior. Understanding the effect of weakly breaking a conservation law due to coherent and incoherent errors is thus crucial, e.g., in the realization of…

Quantum Gases · Physics 2020-10-02 Jad C. Halimeh , Philipp Hauke

An extension of the CCS-method [Chem. Phys. 2004, 304, p. 103-120] for simulating non-adiabatic dynamics with quantum effects of the nuclei is put forward. The time-dependent Schr\"{o}dinger equation for the motion of the nuclei is solved…

Chemical Physics · Physics 2016-07-27 Alexander Humeniuk , Roland Mitrić

Nonadiabatic molecular dynamics is a key technique for investigating a broad range of photochemical and photophysical processes. Among the established approaches, surface hopping schemes are widely used and can be easily integrated with…

Chemical Physics · Physics 2025-12-23 Jakub Martinka , Mikołaj Martyka , Biman Medhi , Jiří Pittner , Pavlo O. Dral

The fractional quantum Hall effect remains a captivating area in condensed matter physics, characterized by strongly correlated topological order, which manifests as fractionalized excitations and anyonic statistics. Numerical simulations,…

Strongly Correlated Electrons · Physics 2025-10-27 Yi Yang , Yayun Hu , Zi-Xiang Hu

Few-shot learning (FSL) enables machine learning models to generalize effectively with minimal labeled data, making it crucial for data-scarce domains such as healthcare, robotics, and natural language processing. Despite its potential, FSL…

Machine Learning · Computer Science 2025-01-24 Rishabh Agrawal