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Related papers: Optimization of the damped quantum search

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A scheme is proposed to estimate the system and environmental parameter, the detuning, temperature and the squeezing strength with a high precision by the two-level atom system. It hasn't been reported that the squeezing strength estimation…

Quantum Physics · Physics 2021-05-07 Mengmeng Luo , Wenxiao Liu , Yuetao Chen , Shaoyan Gao

A quantum algorithm is known that solves an unstructured search problem in a number of iterations of order $\sqrt{d}$, where $d$ is the dimension of the search space, whereas any classical algorithm necessarily scales as $O(d)$. It is shown…

Quantum Physics · Physics 2009-10-31 N. J. Cerf , L. K. Grover , C. P. Williams

This paper discusses an improvement to Grover's algorithm for searches where target states are Hamming weight eigenstates and search space is not ordered. It is shown that under these conditions search efficiency depends on the smaller…

Quantum Physics · Physics 2020-10-09 Jiang Liu

The search of an unstructured database amounts to finding one element having a certain property out of $N$ elements. The classical search with an oracle checking one element at a time requires on average $N/2$ steps. The Grover algorithm…

Quantum Physics · Physics 2022-04-05 Armen E. Allahverdyan , David Petrosyan

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

This article introduces an enhancement to the Grover search algorithm to speed up computing the probability of finding good states. It suggests incorporating a rotation phase angle determined mathematically from the derivative of the model…

Quantum Physics · Physics 2024-05-13 Ismael Abdulrahman

The partial adiabatic search algorithm was introduced in [A. Tulsi, Phys. Rev. A 80, 052328 (2009)] as a modification of the usual adiabatic algorithm for quantum search with the idea that most of the interesting computation only happens…

Quantum Physics · Physics 2013-11-25 Alastair Kay

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 invoke an efficient search algorithms as a key challenge in multi-qubit quantum systems. An original algorithm called dynamical quantum search algorithm from which Grover algorithm is obtained at a specified time is presented. This…

Quantum Physics · Physics 2015-09-17 A. H. Homid , Mahmoud Abdel-Aty , A. -S. F. Obada

The quantum search algorithm consists of an alternating sequence of selective inversions and diffusion type operations, as a result of which it can find a target state in an unsorted database of size N in only sqrt(N) queries. This paper…

Quantum Physics · Physics 2013-05-29 Lov K. Grover

The expectation-maximization (EM) algorithm is a well-known iterative method for computing maximum likelihood estimates from incomplete data. Despite its numerous advantages, a main drawback of the EM algorithm is its frequently observed…

Computation · Statistics 2018-08-14 Nicholas C. Henderson , Ravi Varadhan

Unstructured search remains as one of the significant challenges in computer science, as classical search algorithms become increasingly impractical for large-scale systems due to their linear time complexity. Quantum algorithms, notably…

Quantum Physics · Physics 2025-05-22 Harishankar Mishra , Asvija Balasubramanyam , Gudapati Naresh Raghava

The success probability of a search of $M$ targets from a database of size $N$, using Grover's search algorithm depends critically on the number of iterations of the composite operation of the oracle followed by Grover's diffusion…

Quantum Physics · Physics 2020-11-24 Simanraj Sadana

We consider the effect of two different environments on the performance of the quantum adiabatic search algorithm, a thermal bath at finite temperature, and a structured environment similar to the one encountered in systems coupled to the…

Quantum Physics · Physics 2017-08-17 Ines de Vega , Mari Carmen Bañuls , A. Pérez

A modification of Tulsi's quantum search algorithm with intermediate measurements of the control is presented. In order to analyze the effect of measurements in quantum searches, a different choice of the angular parameter is used. The…

In this paper, we consider the parameterized quantum query complexity for graph problems. We design parameterized quantum query algorithms for $k$-vertex cover and $k$-matching problems, and present lower bounds on the parameterized quantum…

Quantum Physics · Physics 2024-08-08 Tatsuya Terao , Ryuhei Mori

The driving force in the pursuit for quantum computation is the exciting possibility that quantum algorithms can be more efficient than their classical analogues. Research on the subject has unraveled several aspects of how that can happen.…

Quantum Physics · Physics 2011-02-11 Apoorva Patel

The problem of detecting anomalies in multiple processes is considered. We consider a composite hypothesis case, in which the measurements drawn when observing a process follow a common distribution with an unknown parameter (vector), whose…

Information Theory · Computer Science 2020-04-22 Bar Hemo , Tomer Gafni , Kobi Cohen , Qing Zhao

We examine how amplitude noise in queries to the oracle degrades a performance of quantum search algorithm. The Grover search and similar techniques are widely used in various quantum algorithms, including cases where rival parties are…

Quantum Physics · Physics 2022-05-26 Alexey E. Rastegin , Anzhelika M. Shemet

High-dimensional dense embeddings have become central to modern Information Retrieval, but many dimensions are noisy or redundant. Recently proposed DIME (Dimension IMportance Estimation), provides query-dependent scores to identify…

Information Retrieval · Computer Science 2026-04-13 Giulio D'Erasmo , Cesare Campagnano , Antonio Mallia , Pierpaolo Brutti , Nicola Tonellotto , Fabrizio Silvestri