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Related papers: Bounds for nonadiabatic transitions

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In a quantum system with a smoothly and slowly varying Hamiltonian, which approaches a constant operator at times $t\to \pm \infty$, the transition probabilities between adiabatic states are exponentially small. They are characterized by an…

Quantum Physics · Physics 2009-10-31 Michael Wilkinson , Michael A. Morgan

A nonlinear Landau-Zener model was proposed recently to describe, among a number of applications, the nonadiabatic transition of a Bose-Einstein condensate between Bloch bands. Numerical analysis revealed a striking phenomenon that…

Quantum Physics · Physics 2009-11-07 Jie Liu , Li-Bin Fu , Bi-Yiao Ou , Shi-Gang Chen , Qian Niu

The crossover from nonadiabatic to adiabatic electron transfer has been theoretically studied under a spin-boson model (dissipative two-state system) description. We present numerically exact data for the thermal transfer rate and the…

Condensed Matter · Physics 2009-11-07 L. Muehlbacher , R. Egger

Adiabatic transformation can be approximated as alternating unitary operators of a Hamiltonian and its parameter derivative as proposed in a gate-based approach to counterdiabatic driving (van Vreumingen, arXiv:2406.08064). In this paper,…

Quantum Physics · Physics 2024-07-18 Takuya Hatomura

Based on the adiabatic geometric phase concerning with density matrix[1] , we extend it to the sub-geometric phase in the non-adiabatic case. It is found that whatever the real part or imaginary part of the sub-geometric phase can play an…

Quantum Physics · Physics 2024-05-20 Zheng-Chuan Wang

We propose an experimentally feasible scheme to achieve quantum computation based on nonadiabatic geometric phase shifts, in which a cyclic geometric phase is used to realize a set of universal quantum gates. Physical implementation of this…

Quantum Physics · Physics 2009-11-07 Shi-Liang Zhu , Z. D. Wang

We investigate the transition of a quantum wave-packet through a one-dimensional avoided crossing of molecular energy levels when the energy levels at the crossing point are tilted. Using superadiabatic representations, and an approximation…

Mathematical Physics · Physics 2010-07-16 Volker Betz , Benjamin D. Goddard

We introduce a shortcut to the adiabatic gate teleportation model of quantum computation. More specifically, we determine fast local counterdiabatic Hamiltonians able to implement teleportation as a universal computational primitive. In…

Quantum Physics · Physics 2016-01-12 Alan C. Santos , Raphael D. Silva , Marcelo S. Sarandy

Electron transfer is an important and fundamental process in chemistry, biology and physics, and has received significant attention in recent years. Perhaps one of the most intriguing questions concerns with the realization of the…

Mesoscale and Nanoscale Physics · Physics 2023-05-30 Bokang Hou , Michael Thoss , Uri Banin , Eran Rabani

It is generally believed that a generic system can be reversibly transformed from one state into another by sufficiently slow change of parameters. A standard argument favoring this assertion is based on a possibility to expand the energy…

Statistical Mechanics · Physics 2008-11-26 Anatoli Polkovnikov , Vladimir Gritsev

Quantum adiabatic evolution is a dynamical evolution of a quantum system under slow external driving. According to the quantum adiabatic theorem, no transitions occur between non-degenerate instantaneous eigen-energy levels in such a…

Quantum Physics · Physics 2015-06-18 Qi Zhang , Jiangbin Gong , Biao Wu

We present a new quantum adiabatic theorem that allows one to rigorously bound the adiabatic timescale for a variety of systems, including those described by unbounded Hamiltonians. Our bound is geared towards the qubit approximation of…

Quantum Physics · Physics 2024-01-17 Evgeny Mozgunov , Daniel A. Lidar

In many quantum technologies adiabatic processes are used for coherent quantum state operations, offering inherent robustness to errors in the control parameters. The main limitation is the long operation time resulting from the requirement…

Quantum Physics · Physics 2019-04-12 A. Vepsäläinen , S. Danilin , G. S. Paraoanu

Applying time-dependent driving is a basic way of quantum control. Driven systems show various dynamics as its time scale is changed due to the different amount of nonadiabatic transitions. The fast-forward scaling theory enables us to…

Quantum Physics · Physics 2023-07-19 Takuya Hatomura

Obtaining adiabatic processes that connect equilibrium states in a given time represents a challenge for mesoscopic systems. In this paper, we explicitly show how to build these finite-time adiabatic processes for an overdamped Brownian…

Mesoscale and Nanoscale Physics · Physics 2020-04-01 C. A. Plata , D. Guéry-Odelin , E. Trizac , A. Prados

We consider an inhomogeneous quantum phase transition across a multicritical point of the XY quantum spin chain. This is an example of a Lifshitz transition with a dynamical exponent z = 2. Just like in the case z = 1 considered in New J.…

Statistical Mechanics · Physics 2010-10-28 Jacek Dziarmaga , Marek M. Rams

We study the assisted adiabatic passage, and equivalently the transitionless quantum driving, as a quantum brachistochrone trajectory. The optimal Hamiltonian for given constraints is constructed from the quantum brachistochrone equation.…

Quantum Physics · Physics 2013-07-19 Kazutaka Takahashi

Adiabatic passage employs a slowly varying time-dependent Hamiltonian to control the evolution of a quantum system along the Hamiltonian eigenstates. For processes of finite duration, the exact time evolving state may deviate from the…

Quantum Physics · Physics 2021-06-18 Albert Benseny , Klaus Mølmer

We decompose the quantum adiabatic evolution as the products of gauge invariant unitary operators and obtain the exact nonadiabatic correction in the adiabatic approximation. A necessary and sufficient condition that leads to adiabatic…

Quantum Physics · Physics 2016-05-12 Zhen-Yu Wang , Martin B. Plenio

In adiabatic quantum computing the aim is to track an eigenstate as the Hamiltonian changes. In the usual setup this is achieved using the natural time-dependent Hamiltonian evolution of the system and the main technical tool is the…

Quantum Physics · Physics 2026-05-29 Joseph Cunningham , Jérémie Roland