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Related papers: Quantum search with variable times

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The present letter proposes a modification in the well known Grover's search algorithm, which searches a database of $N$ unsorted items in $O(\sqrt{N/M})$ steps, where $M$ represents the number of solutions to the search problem.…

Quantum Physics · Physics 2014-07-11 A. S. Gupta , A. Pathak

In the multitarget Grover algorithm, we are given an unstructured N-element list of objects S_i containing a T-element subset tau and function f, called an oracle, such that f(S_i)=1 if S_i is in tau, otherwise f(S_i) = 0. By using quantum…

Quantum Physics · Physics 2013-05-29 Keith Kastella , Richard Freeling

We present two new quantum algorithms that either find a triangle (a copy of $K_{3}$) in an undirected graph $G$ on $n$ nodes, or reject if $G$ is triangle free. The first algorithm uses combinatorial ideas with Grover Search and makes…

Quantum Physics · Physics 2007-05-23 Frederic Magniez , Miklos Santha , Mario Szegedy

Traditional tree search algorithms supply a blueprint for modeling problem solving behaviour. A diverse spectrum of problems can be formulated in terms of tree search. Quantum computation, in particular Grover's algorithm, has aroused a…

Data Structures and Algorithms · Computer Science 2015-02-09 Luís Tarrataca , Andreas Wichert

We generalize Grover's unstructured quantum search algorithm to enable it to use an arbitrary starting superposition and an arbitrary unitary matrix simultaneously. We derive an exact formula for the probability of the generalized Grover's…

Quantum Physics · Physics 2008-12-18 Robert Gingrich , Colin P. Williams , Nicolas Cerf

Spatial search is the problem of finding a marked vertex in a graph. A continuous-time quantum walk in the single-excitation subspace of an $n$ spin system solves the problem of spatial search by finding the marked vertex in $O(\sqrt{n})$…

Quantum Physics · Physics 2024-10-10 Dylan Lewis , Leonardo Banchi , Sougato Bose

Grover's algorithm has achieved great success. But quantum search algorithms still are not complete algorithms because of Grover's Oracle. We concerned on this problem and present a new quantum search algorithm in adiabatic model without…

Quantum Physics · Physics 2009-09-29 Nanyang Xu , Jin Zhu , Xinhua Peng , Xianyi Zhou , Jiangfeng Du

An algebraic analysis of Grover's quantum search algorithm is presented for the case in which the initial state is an arbitrary pure quantum state of n qubits. This approach reveals the geometrical structure of the quantum search process,…

Quantum Physics · Physics 2009-11-11 D. Shapira , Y. Shimoni , O. Biham

This work considers a generalization of Grover's search problem, viz., to find any one element in a set of acceptable choices which constitute a fraction f of the total number of choices in an unsorted data base. An infinite family of…

Quantum Physics · Physics 2009-11-07 Chia-Ren Hu

We propose a quantum algorithm for closest pattern matching which allows us to search for as many distinct patterns as we wish in a given string (database), requiring a query function per symbol of the pattern alphabet. This represents a…

Quantum Physics · Physics 2007-05-23 P. Mateus , Y. Omar

We introduce an iterative method to search for time-optimal Hamiltonians that drive a quantum system between two arbitrary, and in general mixed, quantum states. The method is based on the idea of progressively improving the efficiency of…

Quantum Physics · Physics 2019-12-25 Francesco Campaioli , William Sloan , Kavan Modi , Felix Alexander Pollock

Grover's algorithm is a quantum search algorithm that proceeds by repeated applications of the Grover operator and the Oracle until the state evolves to one of the target states. In the standard version of the algorithm, the Grover operator…

Quantum Physics · Physics 2018-03-14 Tim Byrnes , Gary Forster , Louis Tessler

We formulate Grover's unstructured search algorithm as a chiral quantum walk, where transitioning in one direction has a phase conjugate to transitioning in the opposite direction. For small phases, this breaking of time-reversal symmetry…

Quantum Physics · Physics 2015-09-22 Thomas G. Wong

The use of superposition of states in quantum computation, known as quantum parallelism, has significant advantage in terms of speed over the classical computation. It can be understood from the early invented quantum algorithms such as…

Quantum Physics · Physics 2017-11-17 Pulak Ranjan Giri , Vladimir E. Korepin

In this work I describe a classical analog of Grover's quantum searching algorithm, explaining why a quantum algorithm should be able to perform search in O(sqrtN) steps and also acting as a useful pedagogic demonstration.

Quantum Physics · Physics 2014-11-25 Shayak Bhattacharjee

We investigate the problem of quantum searching on a noisy quantum computer. Taking a 'fault-ignorant' approach, we analyze quantum algorithms that solve the task for various different noise strengths, which are possibly unknown beforehand.…

Quantum Physics · Physics 2014-07-28 Peter Vrana , David Reeb , Daniel Reitzner , Michael M. Wolf

Quantum random walks on graphs have been shown to display many interesting properties, including exponentially fast hitting times when compared with their classical counterparts. However, it is still unclear how to use these novel…

Quantum Physics · Physics 2009-11-07 Neil Shenvi , Julia Kempe , K. Birgitta Whaley

The Grover algorithm is a crucial solution for addressing unstructured search problems and has emerged as an essential quantum subroutine in various complex algorithms. By using a different approach with previous studies, this research…

Quantum Physics · Physics 2024-12-04 Yifan Sun , Lian-Ao Wu

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

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