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The landmark Grover algorithm for amplitude amplification serves as an essential subroutine in various type of quantum algorithms, with guaranteed quantum speedup in query complexity. However, there have been no proposal to realize the…

Quantum Physics · Physics 2022-03-28 Hiroyuki Tezuka , Kouhei Nakaji , Takahiko Satoh , Naoki Yamamoto

We consider the problem of search of an unstructured list for a marked element, when one is given advice as to where this element might be located, in the form of a probability distribution. The goal is to minimise the expected number of…

Quantum Physics · Physics 2012-08-02 Ashley Montanaro

We provide a tight analysis of Grover's recent algorithm for quantum database searching. We give a simple closed-form formula for the probability of success after any given number of iterations of the algorithm. This allows us to determine…

Quantum Physics · Physics 2015-06-26 Michel Boyer , Gilles Brassard , Peter Hoeyer , Alain Tapp

The Grover search algorithm performs an unstructured search of a marked item in a database quadratically faster than classical algorithms and is shown to be optimal. Here, we show that if the search space is divided into two blocks with the…

Quantum Physics · Physics 2023-12-12 Akankshya Dash , Biswaranjan Panda , Arun K Pati

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

Amplitude amplification is one of primary tools in building algorithms for quantum computers. This technique generalizes key ideas of the Grover search algorithm. Potentially useful modifications are connected with changing phases in the…

Quantum Physics · Physics 2018-07-04 Alexey E. Rastegin

A new approach to the classical limit of Grover's algorithm is discussed by assuming a very rapid dephasing of a system between consecutive Grover's unitary operations, which drives pure quantum states to decohered mixed states. One can…

Quantum Physics · Physics 2019-03-27 Kazuo Fujikawa , C. H. Oh , Koichiro Umetsu

Grover discovered a quantum algorithm for identifying a target element in an unstructured search universe of N items in approximately square-root of N queries to a quantum oracle, thus achieving a square-root speed-up over classical…

Quantum Physics · Physics 2007-05-23 Erdal Arikan

Grover's quantum search algorithm provides a quadratic speedup over the classical one. The computational complexity is based on the number of queries to the oracle. However, depth is a more modern metric for noisy intermediate-scale quantum…

Quantum Physics · Physics 2020-03-31 Kun Zhang , Vladimir E. Korepin

We assess the potential of quantum computing to accelerate computation of central tasks in genomics, focusing on often-neglected theoretical limitations. We discuss state-of-the-art challenges of quantum search, optimization, and machine…

Quantum Physics · Physics 2026-01-09 Aurora Maurizio , Guglielmo Mazzola

Shor's and Grover's famous quantum algorithms for factoring and searching show that quantum computers can solve certain computational problems significantly faster than any classical computer. We discuss here what quantum computers_cannot_…

Quantum Physics · Physics 2015-06-02 Peter Hoyer , Robert Spalek

We operate a superconducting quantum processor consisting of two tunable transmon qubits coupled by a swapping interaction, and equipped with non destructive single-shot readout of the two qubits. With this processor, we run the Grover…

Quantum Physics · Physics 2011-10-25 A. Dewes , R. Lauro , F. R. Ong , V. Schmitt , P. Milman , P. Bertet , D. Vion , D. Esteve

Quantum search is among the most important algorithms in quantum computing. At its core is quantum amplitude amplification, a technique that achieves a quadratic speedup over classical search by combining two global reflections: the oracle,…

Quantum Physics · Physics 2026-05-05 John Burke , Ciaran McGoldrick

We create a variety of new quantum algorithms that use Grover's algorithm and similar techniques to give polynomial speedups over their classical counterparts. We begin by introducing a set of tools that carefully minimize the impact of…

Quantum Physics · Physics 2007-05-23 Bartholomew Furrow

Grover's Search algorithm was a breakthrough at the time it was introduced, and its underlying procedure of amplitude amplification has been a building block of many other algorithms and patterns for extracting information encoded in…

Quantum Physics · Physics 2020-05-27 Austin Gilliam , Marco Pistoia , Constantin Gonciulea

In 1998, Brassard, Hoyer, Mosca, and Tapp (BHMT) gave a quantum algorithm for approximate counting. Given a list of $N$ items, $K$ of them marked, their algorithm estimates $K$ to within relative error $\varepsilon$ by making only $O\left(…

Quantum Physics · Physics 2021-11-05 Scott Aaronson , Patrick Rall

One of the significant breakthroughs in quantum computation is Grover's algorithm for unsorted database search. Recently, the applications of Grover's algorithm to solve global optimization problems have been demonstrated, where unknown…

Quantum Physics · Physics 2017-11-22 Yan Wang

Quantum machine learning algorithms could provide significant speed-ups over their classical counterparts; however, whether they could also achieve good generalization remains unclear. Recently, two quantum perceptron models which give a…

Quantum Physics · Physics 2022-06-22 Mathieu Roget , Giuseppe Di Molfetta , Hachem Kadri

Quantum algorithms can deliver asymptotic speedups over their classical counterparts. However, there are few cases where a substantial quantum speedup has been worked out in detail for reasonably-sized problems, when compared with the best…

Quantum Physics · Physics 2019-07-24 Earl Campbell , Ankur Khurana , Ashley Montanaro

We prove that the generic quantum speedups for brute-force search and counting only hold when the process we apply them to can be efficiently inverted. The algorithms speeding up these problems, amplitude amplification and amplitude…

Quantum Physics · Physics 2026-04-27 Ewin Tang , John Wright