English
Related papers

Related papers: Making peace with random phases: Ab initio conical…

200 papers

We show that a noncyclic phase of geometric origin has to be included in the approximate adiabatic wave function. The adiabatic noncyclic geometric phase for systems exhibiting a conical intersection as well as for an Aharonov-Bohm…

Quantum Physics · Physics 2009-10-31 Gonzalo Garcia de Polavieja , Erik Sjoeqvist

We build on the concept of eigenvector continuation to develop an efficient multi-state method for the rigorous and smooth interpolation of a small training set of many-body wavefunctions through chemical space at mean-field cost. The…

Chemical Physics · Physics 2024-05-02 Kemal Atalar , Yannic Rath , Rachel Crespo-Otero , George H. Booth

The global many-electron wave function overlap matrix accounts for all effects beyond the Born-Oppenheimer approximation in the discrete variable local diabatic representation, a numerically exact framework for modeling nonadiabatic conical…

Chemical Physics · Physics 2025-01-10 Yujuan Xie , Bing Gu

A typical goal of a quantum simulation is to find the energy levels and eigenstates of a given Hamiltonian. This can be realized by adiabatically varying the system control parameters to steer an initial eigenstate into the eigenstate of…

Quantum Physics · Physics 2021-01-04 Gian Salis , Nikolaj Moll , Marco Roth , Marc Ganzhorn , Stefan Filipp

Conical intersections are ubiquitous in chemistry and physics, often governing processes such as light harvesting, vision, photocatalysis, and chemical reactivity. They act as funnels between electronic states of molecules, allowing rapid…

We examine time-resolved X-ray diffraction from molecules in the gas phase which undergo nonadiabatic avoided-crossing dynamics involving strongly coupled electrons and nuclei. Several contributions to the signal are identified,…

Chemical Physics · Physics 2017-05-30 Markus Kowalewski , Kochise Bennett , Shaul Mukamel

We study spin-phonon coupled dynamics in the vicinity of a sloped conical intersection created by laser coupling the electronic (spin) and vibrational degrees of freedom of a pair of trapped Rydberg ions. We show that the shape of the…

Atomic Physics · Physics 2025-12-05 Abdessamad Belfakir , Weibin Li

We introduce an operational framework to analyze non-adiabatic Abelian and non-Abelian, cyclic and non-cyclic, geometric phases in open quantum systems. In order to remove the adiabaticity condition, we generalize the theory of dynamical…

Quantum Physics · Physics 2009-11-13 M. S. Sarandy , E. I. Duzzioni , M. H. Y. Moussa

We argue the feasibility to study the phase structure of a quantum physical system on quantum devices via adiabatic preparation of states. We introduce a novel method and successfully test it in application to the Schwinger model in the…

High Energy Physics - Lattice · Physics 2024-12-11 Oleg Kaikov , Theo Saporiti , Vasily Sazonov , Mohamed Tamaazousti

The effect due to the inter-subsystem coupling on the off-diagonal geometric phase in a composite system is investigated. We analyze the case where the system undergo an adiabatic evolution. Two coupled qubits driven by time-dependent…

Quantum Physics · Physics 2009-11-10 X. X. Yi , J. L. Chang

We introduce an adiabatic perturbation theory for quantum systems with degenerate energy spectra. This perturbative series enables one to rigorously establish conditions for the validity of the adiabatic theorem of quantum mechanics for…

Quantum Physics · Physics 2015-05-18 Gustavo Rigolin , Gerardo Ortiz

We show that techniques of spatial adiabatic passage can be used to realise an electron interferometer in a geometry analogous to a conventional Aharonov-Bohm ring, with transport of the particle through the device modulated using coherent…

Quantum Physics · Physics 2013-05-29 Lenneke M Jong , Andrew D. Greentree

Many physically interesting models show a quantum phase transition when a single parameter is varied through a critical point, where the ground state and the first excited state become degenerate. When this parameter appears as a coupling…

Quantum Physics · Physics 2008-09-24 Gernot Schaller

The Ehrenfest with collapse-to-a-block (TAB) molecular dynamics approach was recently introduced to allow accurate simulation of nonadiabatic dynamics on many electronic states. Previous benchmarking work has demonstrated it to be highly…

Chemical Physics · Physics 2024-11-20 Fangchun Liang , Benjamin G. Levine

Adequate simulation of non-adiabatic dynamics through conical intersection requires account for a non-trivial geometric phase (GP) emerging in electronic and nuclear wave-functions in the adiabatic representation. Popular mixed…

Chemical Physics · Physics 2015-07-20 Rami Gherib , Ilya G. Ryabinkin , Artur F. Izmaylov

We introduce a self-consistent framework for the analysis of both Abelian and non-Abelian geometric phases associated with open quantum systems, undergoing cyclic adiabatic evolution. We derive a general expression for geometric phases,…

Quantum Physics · Physics 2007-05-23 M. S. Sarandy , D. A. Lidar

We have developed an adiabatic Abelian geometric quantum computation strategy based on the non-degenerate energy eigenstates in (but not limited to) superconducting phase-qubit systems. The fidelity of the designed quantum gate was…

Quantum Physics · Physics 2007-08-07 Z. H. Peng , H. F. Chu , Z. D. Wang , D. N. Zheng

The application of adiabatic protocols in quantum technologies is severely limited by environmental sources of noise and decoherence. Shortcuts to adiabaticity by counterdiabatic driving constitute a powerful alternative that speed up…

Quantum Physics · Physics 2019-07-12 Shuoming An , Dingshun Lv , Adolfo del Campo , Kihwan Kim

Quantum molecular dynamics requires an accurate representation of the molecular potential energy surface from a minimal number of electronic structure calculations, particularly for nonadiabatic dynamics where excited states are required.…

Chemical Physics · Physics 2016-08-24 Charles W. Heaps , David A. Mazziotti

We present a new formulation of the correlated electron-ion dynamics (CEID) scheme, which systematically improves Ehrenfest dynamics by including quantum fluctuations around the mean-field atomic trajectories. We show that the method can…

Materials Science · Physics 2007-12-13 L. Stella , M. Meister , A. J. Fisher , A. P. Horsfield