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We investigate the performance of Grover's quantum search algorithm on a register which is subject to loss of the particles that carry the qubit information. Under the assumption that the basic steps of the algorithm are applied correctly…

Quantum Physics · Physics 2012-10-23 D. D. Bhaktavatsala Rao , Klaus Mølmer

Grover's quantum algorithm improves any classical search algorithm. We show how random Gaussian noise at each step of the algorithm can be modelled easily because of the exact recursion formulas available for computing the quantum amplitude…

Quantum Physics · Physics 2009-10-31 B. Pablo-Norman , M. Ruiz-Altaba

As various quantum computing technologies continue to compete for quantum supremacy, several parameters have emerged as benchmarks for the quality of qubits. These include fidelity, coherence times, connectivity, and a few others. In this…

Quantum Physics · Physics 2020-03-04 Daniel Koch , Avery Torrance , David Kinghorn , Saahil Patel , Laura Wessing , Paul M. Alsing

It has recently been shown that there are efficient algorithms for quantum computers to solve certain problems, such as prime factorization, which are intractable to date on classical computers. The chances for practical implementation,…

Quantum Physics · Physics 2009-10-30 Adriano Barenco , Todd A. Brun , Ruediger Schack , Tim Spiller

We study the effects of dissipation or leakage on the time evolution of Grover's algorithm for a quantum computer. We introduce an effective two-level model with dissipation and randomness (imperfections), which is based upon the idea that…

Quantum Physics · Physics 2007-05-23 Pil Hun Song , Ilki Kim

An examination of the concept of using classical degrees of freedom to drive the evolution of quantum computers is given. Specifically, when externally generated, coherent states of the electromagnetic field are used to drive transitions…

Quantum Physics · Physics 2009-10-31 Jeff P. Barnes , Warren S. Warren

Decoherence of quantum states is a major hurdle towards scalable and reliable quantum computing. Lower decoherence (i.e., higher fidelity) can alleviate the error correction overhead and obviate the need for energy-intensive noise reduction…

Emerging Technologies · Computer Science 2019-04-10 Abdullah Ash Saki , Mahabubul Alam , Swaroop Ghosh

We propose a quantum algorithm which uses the number of qubits in an optimal way and efficiently simulates a physical model with rich and complex dynamics described by the quantum sawtooth map. The numerical study of the effect of static…

Quantum Physics · Physics 2007-05-23 Giuliano Benenti , Giulio Casati , Simone Montangero , Dima L. Shepelyansky

A Quantum Computer is a new type of computer which can solve problems such as factoring and database search very efficiently. The usefulness of a quantum computer is limited by the effect of two different types of errors, decoherence and…

Quantum Physics · Physics 2007-05-23 Kevin M. Obenland , Alvin M. Despain

Encoding quantum information in a quantum error correction (QEC) code enhances protection against errors. Imperfection of quantum devices due to decoherence effects will limit the fidelity of quantum gate operations. In particular, neutral…

Quantum Physics · Physics 2026-03-03 J. J. Postema , S. J. J. M. F. Kokkelmans

We generalize Grover algorithm with two arbitrary phases in a density matrix set up. We give exact analytic expressions for the success probability after arbitrary number of iteration of the generalized Grover operator as a function of…

Quantum Physics · Physics 2022-08-01 Saptarshi Roy Chowdhury , Swarupananda Pradhan

Besides the superior efficiency compared to their classical counterparts, quantum algorithms known so far are basically task-dependent, and scarcely any common features are shared between them. In this work, however, we show that the…

Quantum Physics · Physics 2019-03-08 Ye-Chao Liu , Jiangwei Shang , Xiangdong Zhang

As the matching condition in Grover search algorithm is transgressed due to inevitable errors in phase inversions, it gives a reduction in maximum probability of success. With a given degree of maximum success, we have derive the…

Quantum Physics · Physics 2007-05-23 Jin-Yuan Hsieh , Che-Ming Li , Der-San Chuu

The stabilizing properties of one-error correcting jump codes are explored under realistic non-ideal conditions. For this purpose the quantum algorithm of the tent-map is decomposed into a universal set of Hamiltonian quantum gates which…

Quantum Physics · Physics 2007-05-23 Oliver Kern , Gernot Alber

The fidelity of quantum operations is often limited by incoherent errors, which typically can be modeled by fundamental Markovian noise processes such as amplitude damping and dephasing. In Phys. Rev. Lett. 129, 150504 (2022;…

Quantum Physics · Physics 2025-04-08 Tahereh Abad , Yoni Schattner , Anton Frisk Kockum , Göran Johansson

We investigate a quantum algorithm which simulates efficiently the quantum kicked rotator model, a system which displays rich physical properties, and enables to study problems of quantum chaos, atomic physics and localization of electrons…

Quantum Physics · Physics 2007-05-23 B. Levi , B. Georgeot , D. L. Shepelyansky

Based on a generic quantum open system model, we study the geometric nature of decoherence by defining a complex-valued geometric phase through stochastic pure states describing non-unitary, non-cyclic and non-adiabatic evolutions. The…

Quantum Physics · Physics 2019-12-11 Da-Wei Luo , Hai-Qing Lin , J. Q. You , Lian-Ao Wu , Rupak Chatterjee , Ting Yu

It was recently shown (quant-ph/9909074) that parasitic random interactions between the qubits in a quantum computer can induce quantum chaos and put into question the operability of a quantum computer. In this work I investigate whether…

Quantum Physics · Physics 2009-11-07 Daniel Braun

The construction of large, coherent quantum systems necessary for quantum computation remains an entreating but elusive goal, due to the ubiquitous nature of decoherence. Recent progress in quantum error correction schemes have given new…

Quantum Physics · Physics 2008-02-03 Isaac L. Chuang , Yoshihisa Yamamoto

The question of which resources drive the advantages in quantum algorithms has long been a fundamental challenge. While entanglement and coherence are critical to many quantum algorithms, our results indicate that they do not fully explain…

Quantum Physics · Physics 2025-11-11 Si-Qi Zhou , Hai Jin , Jin-Min Liang , Shao-Ming Fei , Yunlong Xiao , Zhihao Ma