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Related papers: Excited state search using quantum annealing

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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

We present a variational quantum adiabatic theorem, which states that, under certain assumptions, the adiabatic dynamics projected onto a variational manifold follow the instantaneous variational ground state. We focus on low-entanglement…

Quantum Physics · Physics 2024-06-19 Bojan Žunkovič , Pietro Torta , Giovanni Pecci , Guglielmo Lami , Mario Collura

Models of quantum computation are important because they change the physical requirements for achieving universal quantum computation (QC). For example, one-way QC requires the preparation of an entangled "cluster" state followed by…

Quantum Physics · Physics 2010-09-28 Dave Bacon , Steven T. Flammia

Quantum annealing is guaranteed to find the ground state of optimization problems in the adiabatic limit. Recent work [Phys. Rev. X 6, 031010 (2016)] has found that for some barrier tunneling problems, quantum annealing can be run much…

Quantum Physics · Physics 2017-04-05 Lucas T. Brady , Wim van Dam

We propose a novel adiabatic time evolution (ATE) method for obtaining the ground state of a quantum many-electron system on a quantum circuit based on first quantization. As a striking feature of the ATE method, it consists of only unitary…

Quantum Physics · Physics 2024-03-18 Yusuke Nishiya , Hirofumi Nishi , Yannick Couzinié , Taichi Kosugi , Yu-ichiro Matsushita

Quantum annealing solves combinatorial optimization problems by finding the energetic ground states of an embedded Hamiltonian. However, quantum annealing dynamics under the embedded Hamiltonian may violate the principles of adiabatic…

Quantum Physics · Physics 2021-04-08 Erica Grant , Travis Humble

Over the last decades, there have been many proposals for quantum computation. One of the promising candidates is adiabatic quantum computation (AQC). The central idea of AQC is about finding the ground state of a system with a problem…

Quantum Physics · Physics 2017-04-12 P. V. Pyshkin , Da-Wei Luo , J. Q. You , Lian-Ao Wu

Quantum annealing aims at solving hard computational problems through adiabatic state preparation. Here, I propose to use inhomogeneous longitudinal magnetic fields to enhance the efficiency of the annealing. Such fields are able to bias…

Quantum Physics · Physics 2019-09-23 Tobias Graß

The preparation of quantum states using short quantum circuits is one of the most promising near-term applications of small quantum computers, especially if the circuit is short enough and the fidelity of gates high enough that it can be…

Quantum Physics · Physics 2015-10-07 D. Wecker , M. B. Hastings , M. Troyer

Quantum computing employs controllable interactions to perform sequences of logical gates and entire algorithms on quantum registers. This paradigm has been widely explored, e.g., for simulating dynamics of manybody systems by decomposing…

Quantum Physics · Physics 2025-05-21 S. Alipour , A. T. Rezakhani , Alireza Tavanfar , K. Mölmer , T. Ala-Nissila

An adiabatic quantum algorithm is essentially given by three elements: An initial Hamiltonian with known ground state, a problem Hamiltonian whose ground state corresponds to the solution of the given problem and an evolution schedule such…

Quantum Physics · Physics 2019-09-17 Davide Pastorello , Enrico Blanzieri

In Phys. Rev. A {\bf 71}, 060312(R) (2005) the robustness of the local adiabatic quantum search to decoherence in the instantaneous eigenbasis of the search Hamiltonian was examined. We expand this analysis to include the case of the global…

Quantum Physics · Physics 2007-05-23 Johan Åberg , David Kult , Erik Sjöqvist

Adiabatic quantum computation is a paradigmatic model aiming to solve a computational problem by finding the many-body ground state encapsulating the solution. However, its use of an adiabatic evolution depending on the spectral gap of an…

Quantum Physics · Physics 2024-06-13 Jaeyoon Cho

Adiabatic quantum annealers encounter scalability challenges due to exponentially fast diminishing energy gaps between ground and excited states with qubit-count increase. This introduces errors in identifying ground states compounded by a…

Quantum Physics · Physics 2024-05-29 Jeung Rac Lee , June-Koo Kevin Rhee , Changjun Kim , Bo Hyun Choi

Computing the excited states of a given Hamiltonian is computationally hard for large systems, but methods that do so using quantum computers scale tractably. This problem is equivalent to the PCA problem where we are interested in…

Quantum Physics · Physics 2025-03-19 David Quiroga , Jason Han , Anastasios Kyrillidis

We introduce two methods for speeding up adiabatic quantum computations by increasing the energy between the ground and first excited states. Our methods are even more general. They can be used to shift a Hamiltonian's density of states…

Quantum Physics · Physics 2015-10-27 Richard Tanburn , Oliver Lunt , Nikesh S. Dattani

We develop a scheme of fast forward of adiabatic spin dynamics of quantum entangled states. We settle the quasi-adiabatic dynamics by adding the regularization terms to the original Hamiltonian and then accelerate it with use of a large…

Quantum Physics · Physics 2018-05-25 Iwan Setiawan , Bobby Eka Gunara , Shumpei Masuda , Katsuhiro Nakamura

We study the glued-trees problem of Childs et. al. in the adiabatic model of quantum computing and provide an annealing schedule to solve an oracular problem exponentially faster than classically possible. The Hamiltonians involved in the…

Quantum Physics · Physics 2013-05-30 Daniel Nagaj , Rolando D. Somma , Maria Kieferova

Quantum simulation with adiabatic annealing can provide insight into difficult problems that are impossible to study with classical computers. However, it deteriorates when the systems scale up due to the shrinkage of the excitation gap and…

Reliable preparation of many-body ground states is an essential task in quantum computing, with applications spanning areas from chemistry and materials modeling to quantum optimization and benchmarking. A variety of approaches have been…

Quantum Physics · Physics 2026-02-09 Ricard Puig , Berta Casas , Alba Cervera-Lierta , Zoë Holmes , Adrián Pérez-Salinas