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Adiabatic optimal control schemes are essential for advancing the practical implementation of quantum technologies. However, the vast array of possible adiabatic protocols, combined with their dependence on the particular quantum system and…

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

We present an adiabatic quantum algorithm for the abstract problem of searching marked vertices in a graph, or spatial search. Given a random walk (or Markov chain) $P$ on a graph with a set of unknown marked vertices, one can define a…

Quantum Physics · Physics 2010-09-08 Hari Krovi , Maris Ozols , Jérémie Roland

We propose a circuit-model quantum algorithm for eigenpath traversal that is based on a combination of concepts from Grover's search and adiabatic quantum computation. Our algorithm deploys a sequence of reflections determined from…

Quantum Physics · Physics 2021-11-11 Jessica Lemieux , Artur Scherer , Pooya Ronagh

We introduce and study the adiabatic dynamics of free-fermion models subject to a local Lindblad bath and in the presence of a time-dependent Hamiltonian. The merit of these models is that they can be solved exactly, and will help us to…

Quantum Physics · Physics 2017-11-20 Maximilian Keck , Simone Montangero , Giuseppe E. Santoro , Rosario Fazio , Davide Rossini

Adiabatic $U(2)$ geometric phases are studied for arbitrary quantum systems with a three-dimensional Hilbert space. Necessary and sufficient conditions for the occurrence of the non-Abelian geometrical phases are obtained without actually…

Quantum Physics · Physics 2008-11-26 Ali Mostafazadeh

Adiabatic quantum algorithms represent a promising approach to universal quantum computation. Whilst in a closed system these algorithms are limited by avoided level crossings, where the gap becomes exponentially small in the system size,…

Quantum Physics · Physics 2016-10-12 Dominik S. Wild , Sarang Gopalakrishnan , Michael Knap , Norman Y. Yao , Mikhail D. Lukin

Open quantum systems described by a non-Hermitian Hamiltonian exhibit rich dynamics due to the topology of their complex energy spectrum. By encircling an exceptional point degeneracy, this topology allows for topological state transport,…

Quantum Physics · Physics 2026-02-25 Serra Erdamar , Maryam Abbasi , Weijian Chen , Niklas Hörnedal , Aurélia Chenu , Kater W. Murch

Quantum annealing is a continuous-time heuristic quantum algorithm for solving or approximately solving classical optimization problems. The algorithm uses a schedule to interpolate between a driver Hamiltonian with an easy-to-prepare…

Recent experiments with increasingly larger numbers of qubits have sparked renewed interest in adiabatic quantum computation, and in particular quantum annealing. A central question that is repeatedly asked is whether quantum features of…

Quantum Physics · Physics 2015-06-22 Tameem Albash , Daniel A. Lidar

We explore the relationship between two figures of merit for an adiabatic quantum computation process: the success probability $P$ and the minimum gap $\Delta_{min}$ between the ground and first excited states, investigating to what extent…

Quantum Physics · Physics 2015-05-28 M. Cullimore , M. J. Everitt , M. A. Ormerod , J. H. Samson , R. D. Wilson , A. M. Zagoskin

The adiabatic approximation in open systems is formulated through the effective Hamiltonian approach. By introducing an ancilla, we embed the open system dynamics into a non-Hermitian quantum dynamics of a composite system, the adiabatic…

Quantum Physics · Physics 2009-11-13 X. X. Yi , D. M. Tong , L. C. Kwek , C. H. OH

Quantum annealing (QA) is a promising approach for not only solving combinatorial optimization problems but also simulating quantum many-body systems such as those in condensed matter physics. However, non-adiabatic transitions constitute a…

Quantum Physics · Physics 2022-09-21 Takashi Imoto , Yuya Seki , Yuichiro Matsuzaki

We propose a strategy for modeling the behavior of an adiabatic quantum computer described by an Ising Hamiltonian with $N$ sites and the coordination number $Z$. The method is based on the $1/Z$ expansion for the density matrix of the…

Quantum Physics · Physics 2018-04-10 Elnaz Darsheshdar , Seyed Mostafa Moniri , Patrick Navez , Alexandre Zagoskin

Designing proper time-dependent control fields for slowly varying the system to the ground state that encodes the problem solution is crucial for adiabatic quantum computation. However, inevitable perturbations in real applications demand…

Quantum Physics · Physics 2020-07-22 Xiaodong Yang , Ran Liu , Jun Li , Xinhua Peng

The Fermi-Hubbard model (FHM) on a two dimensional square lattice has long been an important testbed and target for simulating fermionic Hamiltonians on quantum hardware. We present an alternative for quantum simulation of FHMs based on an…

The main challenges in achieving high-fidelity quantum gates are to reduce the influence of control errors caused by imperfect Hamiltonians and the influence of decoherence caused by environment noise. To overcome control errors, a…

Quantum Physics · Physics 2020-07-01 P. Z. Zhao , K. Z. Li , G. F. Xu , D. M. Tong

Shortcuts to adiabaticity are alternative fast processes which reproduce the same final state as the adiabatic process in a finite or even shorter time, which have been extended from Hermitian systems to non-Hermitian systems in recent…

Quantum Physics · Physics 2024-04-15 T. Z. Luan , H. Z. Shen , X. X. Yi

Adiabatic quantum optimization has attracted a lot of attention because small scale simulations gave hope that it would allow to solve NP-complete problems efficiently. Later, negative results proved the existence of specifically designed…

Quantum Physics · Physics 2009-12-02 Boris Altshuler , Hari Krovi , Jeremie Roland

Recent advances in the field of adiabatic quantum computing and the closely related field of quantum annealers has centered around using more advanced and novel Hamiltonian representations to solve optimization problems. One of these…

Quantum Physics · Physics 2022-07-12 Hannes Leipold , Federico M. Spedalieri