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In order to understand the bounds of utilization of the Grover's search algorithm for the large unstructured data in presence of the quantum computer noise, we undertake a series of simulations by inflicting various types of noise, modelled…

Quantum Physics · Physics 2020-10-28 Yulun Wang , Predrag S. Krstic

The Grover search algorithm is a pivotal advancement in quantum computing, promising a remarkable speedup over classical algorithms in searching unstructured large databases. Here, we report results for the implementation and…

Quantum Physics · Physics 2025-01-14 M. AbuGhanem

This paper concerns the Grover algorithm that permits to make amplification of quantum states previously tagged by an Oracle. Grover's algorithm allows searches in an unstructure database of n entries finding a marked element with a…

Quantum Physics · Physics 2022-11-08 Gérard Fleury , Philippe Lacomme

Since Grover's seminal work which provides a way to speed up combinatorial search, quantum search has been studied in great detail. We propose a new method for designing quantum search algorithms for finding a marked element in the state…

Quantum Physics · Physics 2012-08-07 R. Sufiani , N. Bahari

We propose a new adiabatic algorithm for the unsorted database search problem. This algorithm saves two thirds of qubits than Grover's algorithm in realizations. Meanwhile, we analyze the time complexity of the algorithm by both…

Quantum Physics · Physics 2008-11-06 Nanyang Xu , Xinhua Peng , Mingjun Shi , Jiangfeng Du

Grover's algorithm provides a quadratic speed-up over classical algorithms for unstructured database or library searches. This paper examines the robustness of Grover's search algorithm to a random phase error in the oracle and analyzes the…

Quantum Physics · Physics 2009-11-10 Neil Shenvi , Kenneth R. Brown , K. Birgitta Whaley

In this work we address two questions concerning Grover's algorithm. In the first we give an answer to the question how to employ Grover's algorithm for actual search over database. We introduce a quantum model of an unordered phone book…

Quantum Physics · Physics 2014-06-26 Daniel Reitzner , Mario Ziman

Grover's quantum algorithm can find a marked item from an unstructured database faster than any classical algorithm, and hence it has been used for several applications such as cryptanalysis and optimization. When there exist multiple…

Quantum Physics · Physics 2025-07-02 Kota Tani , Shunji Tsuchiya , Seiichiro Tani , Yuki Takeuchi

Grover's database search algorithm is the optimal algorithm for finding a desired object from an unsorted collection of items. Although it was discovered in the context of quantum computation, it is simple and versatile enough to be…

General Physics · Physics 2007-12-03 Aavishkar A. Patel

For the unsorted database quantum search with the unknown fraction $\lambda$ of target items, there are mainly two kinds of methods, i.e., fixed-point or trail-and-error. (i) In terms of the fixed-point method, Yoder et al. [Phys. Rev.…

Quantum Physics · Physics 2019-12-05 Tan Li , Shuo Zhang , Xiang-Qun Fu , Xiang Wang , Yang Wang , Jie Lin , Wan-Su Bao

Grover's quantum search algorithm promises a quadratic speedup for unstructured search over its classical counterpart. But this advantage is affected by noise acting on the search space. Here, we show that a quantum switch can act as a…

Quantum Physics · Physics 2025-05-13 Suryansh Srivastava , Arun K. Pati , Samyadeb Bhattacharya , Indranil Chakrabarty

External environment influences on Grover's search algorithm modeled by quantum noise are investigated. The algorithm is shown to be robust under that external dissipation. Explicitly we prove that the resulting search positive maps acting…

Quantum Physics · Physics 2007-05-23 Demosthenes Ellinas , Christos Konstadakis

This paper researches how the systematic errors in phase inversions affect the success rate and the number of iterations in optimized quantum random-walk search algorithm. Through geometric description of this algorithm, the model of the…

Quantum Physics · Physics 2015-01-12 Yu-Chao Zhang , Wan-Su Bao , Xiang Wang , Xiang-Qun Fu

The task of finding an entry in an unsorted list of $N$ elements famously takes $O(N)$ queries to an oracle for a classical computer and $O(\sqrt{N})$ queries for a quantum computer using Grover's algorithm. Reformulated as a spatial search…

Quantum Physics · Physics 2022-01-04 Thomas G. Wong

Given two unsorted lists each of length N that have a single common entry, a quantum computer can find that matching element with a work factor of $O(N^{3/4}\log N)$ (measured in quantum memory accesses and accesses to each list). The…

Quantum Physics · Physics 2007-05-23 Mark Heiligman

With reference to a search in a database of size N, Grover states: "What is the reason that one would expect that a quantum mechanical scheme could accomplish the search in O(square root of N) steps? It would be insightful to have a simple…

Quantum Physics · Physics 2009-11-13 Giuseppe Castagnoli

Grover's algorithm, a well-know quantum search algorithm, allows one to find the correct item in a database, with quadratic speedup. In this paper we adapt Grover's algorithm to the problem of finding a correct answer to a natural language…

Quantum Physics · Physics 2022-01-28 A. D. Correia , M. Moortgat , H. T. C. Stoof

A quantum algorithm is a set of instructions for a quantum computer, however, unlike algorithms in classical computer science their results cannot be guaranteed. A quantum system can undergo two types of operation, measurement and quantum…

Data Structures and Algorithms · Computer Science 2007-05-30 Eva Borbely

An ideal quantum walk transitions from one vertex to another with perfect fidelity, but in physical systems, the particle may be hindered by potential energy barriers. Then the particle has some amplitude of tunneling through the barriers,…

Quantum Physics · Physics 2016-11-10 Thomas G. Wong

In a recent paper (quant-ph/0506105), A S Gupta, M. Gupta and A. Pathak proposed a modified Grover algorithm that would exponentially accelerate the unsorted database search problem if the number of marked items is known. If this were true,…

Quantum Physics · Physics 2007-05-23 Gui Lu Long