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Related papers: Adiabatic optimization without local minima

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We prove an adiabatic theorem that applies at timescales short of the typical adiabatic limit. Our proof analyzes the stability of solutions to Schrodinger's equation under perturbation. We directly characterize cross-subspace effects of…

Quantum Physics · Physics 2024-10-21 Jacob Bringewatt , Michael Jarret , T. C. Mooney

We introduce a geometric framework for efficient few-parameter pulse optimization in multi-level quantum systems, enabling high-fidelity state transfer beyond the adiabatic limit. Our method interpolates smoothly between adiabatic and…

Quantum fluctuations driven by non-stoquastic Hamiltonians have been conjectured to be an important and perhaps essential missing ingredient for achieving a quantum advantage with adiabatic optimization. We introduce a transformation that…

Quantum Physics · Physics 2020-09-30 Elizabeth Crosson , Tameem Albash , Itay Hen , A. P. Young

We present an optimized adiabatic quantum schedule for unstructured search building on the original approach of Roland and Cerf [Phys. Rev. A 65, 042308 (2002)]. Our schedule adiabatically varies the Hamiltonian even more rapidly at the…

Quantum Physics · Physics 2025-02-13 Sean A. Adamson , Petros Wallden

Consider a path of non-degenerate eigenstates of unitary operators or Hamiltonians with minimum eigenvalue gap G. The eigenpath traversal problem is to transform one or more copies of the initial to the final eigenstate. Solutions to this…

Quantum Physics · Physics 2015-03-17 S. Boixo , E. Knill , R. D. Somma

Fixed-point quantum search algorithms succeed at finding one of $M$ target items among $N$ total items even when the run time of the algorithm is longer than necessary. While the famous Grover's algorithm can search quadratically faster…

Quantum Physics · Physics 2017-02-07 Alexander M. Dalzell , Theodore J. Yoder , Isaac L. Chuang

Grover's unstructured search algorithm is one of the best examples to date for the superiority of quantum algorithms over classical ones. Its applicability, however, has been questioned by many due to its oracular nature. We propose a…

Quantum Physics · Physics 2017-08-21 Itay Hen

Most investigations devoted to the conditions for adiabatic quantum computing are based on the first-order correction ${\bra{\Psi_{\rm ground}(t)}\dot H(t)\ket{\Psi_{\rm excited}(t)} /\Delta E^2(t)\ll1}$. However, it is demonstrated that…

Quantum Physics · Physics 2009-11-11 Gernot Schaller , Sarah Mostame , Ralf Schützhold

Much research regarding quantum adiabatic optimization has focused on stoquastic Hamiltonians with Hamming symmetric potentials, such as the well studied "spike" example. Due to the large amount of symmetry in these potentials such problems…

Quantum Physics · Physics 2020-10-05 Jacob Bringewatt , William Dorland , Stephen P. Jordan

The quantum adiabatic unstructured search algorithm is one of only a handful of quantum adiabatic optimization algorithms to exhibit provable speedups over their classical counterparts. With no fault tolerance theorems to guarantee the…

Quantum Physics · Physics 2019-11-14 Mikhail Slutskii , Tameem Albash , Lev Barash , Itay Hen

Existing quantum algorithms for quantum chemistry work well near the equilibrium geometry of molecules, but the results can become unstable when the chemical bonds are broken at large atomic distances. For any adiabatic approach, this…

Chemical Physics · Physics 2023-05-09 Hongye Yu , Deyu Lu , Qin Wu , Tzu-Chieh Wei

Quantum computation has revolutionary potential for speeding algorithms and for simulating quantum systems such as molecules. We report here a quantum computer design that performs universal quantum computation within a single…

Quantum Physics · Physics 2014-01-22 Ari Mizel

We have developed a general technique to study the dynamics of the quantum adiabatic evolution algorithm applied to random combinatorial optimization problems in the asymptotic limit of large problem size $n$. We use as an example the…

Quantum Physics · Physics 2007-05-23 Vadim N. Smelyanskiy , Udo v. Toussaint , Dogan A. Timucin

We show that, during adiabatic evolution, any changes in entanglement can be attributed to a succession of avoided energy level crossings at which eigenvalues swap their eigenvectors. These swaps mediate the generation and redistribution of…

Quantum Physics · Physics 2025-08-14 Einar Gabbassov , Achim Kempf

Surface hopping algorithms, as an important class of quantum dynamics simulation algorithms for non-adiabatic dynamics, are typically performed in the adiabatic representation, which can break down in the presence of ill-defined adiabatic…

Numerical Analysis · Mathematics 2022-05-06 Zhenning Cai , Di Fang , Jianfeng Lu

We show that adiabatic evolution of a low-dimensional lattice of quantum spins with a spectral gap can be simulated efficiently. In particular, we show that as long as the spectral gap \Delta E between the ground state and the first excited…

Quantum Physics · Physics 2007-05-23 Tobias J. Osborne

We study the typical (median) value of the minimum gap in the quantum version of the Exact Cover problem using Quantum Monte Carlo simulations, in order to understand the complexity of the quantum adiabatic algorithm (QAA) for much larger…

Disordered Systems and Neural Networks · Physics 2009-11-13 A. P. Young , S. Knysh , V. N. Smelyanskiy

We present a 2-local quantum algorithm for graph isomorphism GI based on an adiabatic protocol. By exploiting continuous-time quantum-walks, we are able to avoid a mere diffusion over all possible configurations and to significantly reduce…

Quantum Physics · Physics 2017-10-13 Dario Tamascelli , Luca Zanetti

A variety of quantum computing algorithms exist for the preparation of approximate Hamiltonian ground states. A natural and important question is how these ground-state approximations can be further improved using adiabatic state…

An important method for search engine result ranking works by finding the principal eigenvector of the "Google matrix." Recently, a quantum algorithm for preparing this eigenvector and evidence of an exponential speedup for some scale-free…