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Related papers: Adiabatic quantum unstructured search in parallel

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We check a recent proposal [H. Goto and K. Ichimura Phys. Rev. A 70, 012305 (2004)] for controlled phase gate through adiabatic passage under the influence of spontaneous emission and the cavity decay. We show a modification of above…

Quantum Physics · Physics 2015-06-26 Z. J. Deng , K. L. Gao , F. Mang

For adiabatic controls of quantum systems, the non-adiabatic transitions are reduced by increasing the operation time of processes. Perfect quantum adiabaticity usually requires the infinitely slow variation of control parameters. In this…

Quantum Physics · Physics 2022-07-01 Jin-Fu Chen

We introduce an algorithm to perform an optimal adiabatic evolution that operates without an apriori knowledge of the system spectrum. By probing the system gap locally, the algorithm maximizes the evolution speed, thus minimizing the total…

Quantum Physics · Physics 2011-05-10 J. Nehrkorn , S. Montangero , A. Ekert , A. Smerzi , R. Fazio , T. Calarco

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 show enough evidence that a structured version of Adiabatic Quantum Computation (AQC) is efficient for most satisfiability problems. More precisely, when the success probability is fixed beforehand, the computational resources grow…

Quantum Physics · Physics 2008-12-10 Juan Jose Garcia-Ripoll , Mari Carmen Bañuls

We report the realization of a nuclear magnetic resonance computer with three quantum bits that simulates an adiabatic quantum optimization algorithm. Adiabatic quantum algorithms offer new insight into how quantum resources can be used to…

Quantum Physics · Physics 2007-05-23 Matthias Steffen , Wim van Dam , Tad Hogg , Greg Breyta , Isaac Chuang

So far, only the results on 3 qubit spaces (both on superconducting and ion-trap realisations of quantum processors) have beaten the classical unstructured search in the expected number of oracle calls using optimal protocols in both…

A typical goal of a quantum simulation is to find the energy levels and eigenstates of a given Hamiltonian. This can be realized by adiabatically varying the system control parameters to steer an initial eigenstate into the eigenstate of…

Quantum Physics · Physics 2021-01-04 Gian Salis , Nikolaj Moll , Marco Roth , Marc Ganzhorn , Stefan Filipp

This thesis investigates quantum algorithms for eigenstate preparation, with a focus on solving eigenvalue problems such as the Schrodinger equation by utilizing near-term quantum computing devices. These problems are ubiquitous in several…

Quantum Physics · Physics 2024-12-20 Joey Bonitati

Grover's algorithm solves the unstructured search problem. Grover's algorithm can find the target state with certainty only if searching one out of four. Designing the deterministic search algorithm can avoid any repetition of the…

Quantum Physics · Physics 2025-01-14 Zhen Wang , Kun Zhang , Vladimir Korepin

Quantum state preparation lies at the heart of quantum computation and quantum simulations, enabling the investigation of complex manybody systems across physics, chemistry, and data science. While existing methods such as Variational…

Quantum Physics · Physics 2026-01-27 Davide Cugini , Giacomo Guarnieri , Mario Motta , Dario Gerace

Analog quantum algorithms are formulated in terms of Hamiltonians rather than unitary gates and include quantum adiabatic computing, quantum annealing, and the quantum approximate optimization algorithm (QAOA). These algorithms are…

We solve the unstructured search problem in constant time by computing with a physically motivated nonlinearity of the Gross-Pitaevskii type. This speedup comes, however, at the novel expense of increasing the time-measurement precision.…

Quantum Physics · Physics 2013-06-14 David A. Meyer , Thomas G. Wong

We introduce an alternative way to derive the generalized form of the master equation recently presented by J. P. Pekola et al. [Phys. Rev. Lett. 105, 030401 (2010)] for an adiabatically steered two-level quantum system interacting with a…

Quantum Physics · Physics 2011-12-22 J. Salmilehto , P. Solinas , J. Ankerhold , M. Möttönen

Recently there have been some controversies about the criterion of the adiabatic approximation. It is shown that an approximate diagonalization of the effective Hamiltonian in the second quantized formulation gives rise to a reliable and…

Quantum Physics · Physics 2008-11-26 Kazuo Fujikawa

We investigate the quantum mechanics of a single particle constrained to move along an arbitrary smooth reference curve by a confinement that is allowed to vary along the waveguide. The Schr\"odinger equation is evaluated in the adapted…

Quantum Physics · Physics 2014-03-26 J. Stockhofe , P. Schmelcher

Adiabatic quantum computation with Rydberg atoms provides a natural route for solving combinatorial optimization problems such as the maximum independent set (MIS). However, its performance is fundamentally limited by the reduction of the…

Quantum Physics · Physics 2026-02-23 Seokho Jeong , Minhyuk Kim

We describe tensor network algorithms to optimize quantum circuits for adiabatic quantum computing. To suppress diabatic transitions, we include counterdiabatic driving in the optimization and utilize variational matrix product operators to…

Quantum Physics · Physics 2024-06-21 Conor Mc Keever , Michael Lubasch

Adiabatic state engineering is a powerful technique in quantum information and quantum control. However, its performance is limited by the adiabatic theorem of quantum mechanics. In this scenario, shortcuts to adiabaticity, such as provided…

Quantum Physics · Physics 2015-11-03 Alan C. Santos , Marcelo S. Sarandy

Grover's quantum algorithm for an unstructured search problem and the Count algorithm by Brassard et al. are generalized to the case when the initial state is arbitrarily and maximally entangled. This ansatz might be relevant with quantum…

Quantum Physics · Physics 2007-05-23 A. Carlini , A. Hosoya