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Related papers: Complex time method for quantum dynamics when an e…

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We study a quantum theory with complex time parameter and non-Hermitian Hamiltonian structure. In this theory, the real part of the complex time is equal to `usual' physical time, whereas the imaginary one is proportional to inverse…

High Energy Physics - Theory · Physics 2007-05-23 Vadim V. Asadov , Oleg V. Kechkin

We consider a composite open quantum system consisting of a fast subsystem coupled to a slow one. Using the time-scale separation, we develop an adiabatic elimination technique to derive at any order the reduced model describing the slow…

Quantum Physics · Physics 2017-07-11 Remi Azouit , Francesca Chittaro , Alain Sarlette , Pierre Rouchon

The Entropic Dynamics reconstruction of quantum mechanics is extended to quantum field theory in curved space-time. The Entropic Dynamics framework, which derives quantum theory as an application of the method of maximum entropy, is…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Selman Ipek , Mohammad Abedi , Ariel Caticha

We consider the adiabatic quantum algorithm for systems with "no sign problem", such as the transverse field Ising mode, and analyze the equilibration time for quantum Monte Carlo (QMC) on these systems. We ask: if the spectral gap is only…

Quantum Physics · Physics 2015-10-05 M. B. Hastings , M. H. Freedman

We propose an adiabatic-elimination formalism in the dispersive regime based on a transition-centric perturbation theory. The perturbative expansion is recast into a diagrammatic framework, while adiabatic elimination is implemented through…

Quantum Physics · Physics 2026-05-15 Mohamed Meguebel , Maxime Federico , Louis Garbe , Nadia Belabas , Nicolas Fabre

This work explores the relationship between optimal control theory and adiabatic passage techniques in quantum systems. The study is based on a geometric analysis of the Hamiltonian dynamics constructed from the Pontryagin Maximum…

Quantum Physics · Physics 2015-06-11 E. Assémat , D. Sugny

We review a scheme for the systematic design of quantum control protocols based on shortcuts to adiabaticity in few-level quantum systems. The adiabatic dynamics is accelerated by introducing high-frequency modulations in the control…

Quantum Physics · Physics 2024-02-08 Francesco Petiziol , Florian Mintert , Sandro Wimberger

On the basis of the closed-time path formalism of non-equilibrium quantum field theory, we derive the real-time quantum dynamics of heavy quark systems. Even though our primary goal is the description of heavy quarkonia, our method allows a…

High Energy Physics - Phenomenology · Physics 2015-06-11 Yukinao Akamatsu

The dynamics of quantum systems under the adiabatic Hamiltonian has attracted attention not only in quantum control but also in a wide range of fields from condensed matter physics to high-energy physics because of its non-perturbative…

Quantum Physics · Physics 2024-05-10 Takayuki Suzuki , Eiki Taniguchi , Kaito Iwamura

Adiabatic quantum computing is a general framework for preparing eigenstates of Hamiltonians on quantum devices. However, its digital implementation requires an efficient Hamiltonian simulation subroutine, which may introduce extra…

Quantum Physics · Physics 2025-09-03 Dong An , Pedro C. S. Costa , Dominic W. Berry

We introduce the concept of a "transitory" dynamical system---one whose time-dependence is confined to a compact interval---and show how to quantify transport between two-dimensional Lagrangian coherent structures for the Hamiltonian case.…

Chaotic Dynamics · Physics 2015-03-17 B. A. Mosovsky , J. D. Meiss

Quantum systems are typically subject to various environmental noise sources. Treating these environmental disturbances with a system-bath approach beyond weak coupling one must refer to numerical methods as, for example, the numerically…

Quantum Physics · Physics 2021-12-08 Timo Palm , Peter Nalbach

The observation that concepts from quantum information has generated many alternative indicators of quantum phase transitions hints that quantum phase transitions possess operational significance with respect to the processing of quantum…

Quantum Physics · Physics 2012-05-08 Jian Cui , Mile Gu , Leong Chuan Kwek , Marcelo França Santos , Heng Fan , Vlatko Vedral

The theoretical investigation of non-adiabatic processes is hampered by the complexity of the coupled electron-nuclear dynamics beyond the Born-Oppenheimer approximation. Classically, the simulation of such reactions is limited by the…

Quantum Physics · Physics 2021-01-06 Pauline J. Ollitrault , Guglielmo Mazzola , Ivano Tavernelli

Time-driven quantum systems are important in many different fields of physics like cold atoms, solid state, optics, etc. Many of their properties are encoded in the time evolution operator which is calculated by using a time-ordered product…

The system undergoes adiabatic evolution when its population in the instantaneous eigenbasis of its time-dependent Hamiltonian changes only negligibly. Realization of such dynamics requires slow-enough changes of the parameters of the…

Quantum Physics · Physics 2015-06-23 Bogdan Damski

The problem Hamiltonian of the adiabatic quantum algorithm for the maximum-weight independent set problem (MIS) that is based on the reduction to the Ising problem (as described in [Choi08]) has flexible parameters. We show that by choosing…

Quantum Physics · Physics 2010-04-14 Vicky Choi

The NP-complete problem of the travelling salesman (TSP) is considered in the framework of quantum adiabatic computation (QAC). We first derive a remarkable lower bound for the computation time for adiabatic algorithms in general as a…

Quantum Physics · Physics 2007-05-23 Tien D. Kieu

We study the dynamics of a pair of atoms, resonantly interacting with a single mode cavity, in the situation where the atoms enter the cavity with a time delay between them. Using time dependent coupling functions to represent the spatial…

Quantum Physics · Physics 2010-10-15 C. Lazarou , B. M. Garraway

We present a perturbative method to estimate the spectral gap for adiabatic quantum optimization, based on the structure of the energy levels in the problem Hamiltonian. We show that for problems that have exponentially large number of…

Quantum Physics · Physics 2009-11-13 M. H. S. Amin