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Related papers: Non-Adiabatic Quantum Optimization for Crossing Qu…

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Quantum adiabatic optimization (QAO) is performed using a time-dependent Hamiltonian $H(s)$ with spectral gap $\gamma(s)$. Assuming the existence of an oracle $\Gamma$ such that $\gamma_\min = \Theta\left(\min_s\Gamma(s)\right)$, we provide…

Quantum Physics · Physics 2019-04-19 Michael Jarret , Brad Lackey , Aike Liu , Kianna Wan

Shortcuts to adiabaticity are well-known methods for controlling the quantum dynamics beyond the adiabatic criteria, where counter-diabatic (CD) driving provides a promising means to speed up quantum many-body systems. In this work, we show…

We present a method for accelerating adiabatic protocols for systems involving a coupling to a continuum, one that cancels both non-adiabatic errors as well as errors due to dissipation. We focus on applications to a generic quantum state…

Quantum Physics · Physics 2017-11-07 Alexandre Baksic , Ron Belyansky , Hugo Ribeiro , Aashish A. Clerk

Transitionless quantum driving, also known as counterdiabatic driving, is a unique shortcut technique to adiabaticity, enabling a fast-forward evolution to the same target quantum states as those in the adiabatic case. However, as nothing…

Quantum Physics · Physics 2018-03-20 Zhen-Yu Xu , Wen-Long You , Yu-Li Dong , Chengjie Zhang , W. L. Yang

Properly designed control has been shown to be particularly advantageous for improving AQC accuracy and time complexity scaling. Here, an \emph{in situ} quantum control optimization protocol is developed to indirectly optimize state…

Quantum Physics · Physics 2019-06-12 Gregory Quiroz

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

Quantum annealing (QA) is an algorithm to find the ground state of the problem Hamiltonian by using an adiabatic time evolution. An approach to evaluate adiabaticity in the experiment by applying spectroscopic techniques has recently been…

Quantum Physics · Physics 2024-08-20 Yuichiro Mori , Harunobu Hiratsuka , Yuichiro Matsuzaki

Finite-time quantum heat engines (QHEs) typically extract less work than their quasistatic counterparts because fast driving generates coherences and non-adiabatic transitions during the work strokes, a phenomenon commonly referred to as…

Quantum Physics · Physics 2026-05-19 Selma Memić , Rafael Wagner , Susana F. Huelga , Martin B. Plenio

The Quantum Approximate Optimization Algorithm and its generalization to Quantum Alternating Operator Ansatz (QAOA) is a promising approach for applying quantum computers to challenging problems such as combinatorial optimization and…

Quantum Physics · Physics 2023-07-25 Vladimir Kremenetski , Anuj Apte , Tad Hogg , Stuart Hadfield , Norm M. Tubman

Quantum computation has emerged as a powerful computational medium of our time, having demonstrated the remarkable efficiency in factoring a positive integer and searching databases faster than any currently known classical computing…

Quantum Physics · Physics 2024-04-16 Tomoyuki Yamakami

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

High-fidelity and robust coherent population transfer is a major challenge in coherent quantum control. Different from the well known adiabatic condition, we present a rigorous adiabatic condition that is inspired by the idea of the…

Quantum Physics · Physics 2019-09-04 Jian Xu , Yan-Xiong Du , Wei Huang

Adiabaticity of quantum evolution is important in many settings. One example is the adiabatic quantum computation. Nevertheless, up to now, there is no effective method to test the adiabaticity of the evolution when the eigenenergies of the…

Quantum Physics · Physics 2010-10-08 H. T. Quan , W. H. Zurek

We study temporal behavior of a quantum system under a slow external perturbation, which drives the system across a second order quantum phase transition. It is shown that despite the conventional adiabaticity conditions are always violated…

Statistical Mechanics · Physics 2007-05-23 Anatoli Polkovnikov

The nonadiabatic dynamics of a many-body system driven through a quantum critical point can be controlled using counterdiabatic driving, where the formation of excitations is suppressed by assisting the dynamics with auxiliary multiple-body…

Quantum Physics · Physics 2014-12-08 Hamed Saberi , Tomáš Opatrný , Klaus Mølmer , Adolfo del Campo

Quantum batteries are energy storage devices that satisfy quantum mechanical principles. How to improve the battery's performance such as stored energy and power is a crucial element in the quantum battery. Here, we investigate the charging…

Quantum Physics · Physics 2021-12-01 Fu-Quan Dou , Yuan-Jin Wang , Jian-An Sun

Computing using a continuous-time evolution, based on the natural interaction Hamiltonian of the quantum computer hardware, is a promising route to building useful quantum computers in the near-term. Adiabatic quantum computing, quantum…

Quantum Physics · Physics 2019-03-06 James G. Morley , Nicholas Chancellor , Sougato Bose , Viv Kendon

The ability to efficiently prepare ground states of quantum Hamiltonians via adiabatic protocols is typically limited by the smallest energy gap encountered during the quantum evolution. This presents a key obstacle for quantum simulation…

The quantum approximate optimization algorithm (QAOA) has proved to be an effective classical-quantum algorithm serving multiple purposes, from solving combinatorial optimization problems to finding the ground state of many-body quantum…

Quantum Physics · Physics 2022-03-08 P. Chandarana , N. N. Hegade , K. Paul , F. Albarrán-Arriagada , E. Solano , A. del Campo , Xi Chen

In this paper we address the question how the Kibble-Zurek mechanism, which describes the formation of topological defects in quantum systems subjected to a quench across a critical point, is generalized to the same scenario but for…

Quantum Physics · Physics 2017-12-06 Patrik Hedvall , Jonas Larson