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Related papers: Quantum Search Algorithms on Hierarchical Networks

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The standard quantum search algorithm lacks a feature, enjoyed by many classical algorithms, of having a fixed-point, i.e. a monotonic convergence towards the solution. Here we present two variations of the quantum search algorithm, which…

Quantum Physics · Physics 2007-05-23 Lov K. Grover , Apoorva Patel , Tathagat Tulsi

We examine the effect of network heterogeneity on the performance of quantum search algorithms. To this end, we study quantum search on a tree for the oracle Hamiltonian formulation employed by continuous-time quantum walks. We use…

Quantum Physics · Physics 2016-03-09 Pascal Philipp , Luís Tarrataca , Stefan Boettcher

Performance of cryptanalytic quantum search algorithms is mainly inferred from query complexity which hides overhead induced by an implementation. To shed light on quantitative complexity analysis removing hidden factors, we provide a…

Cryptography and Security · Computer Science 2018-11-02 Panjin Kim , Kyung Chul Jeong , Daewan Han

The coined quantum walk is a discretization of the Dirac equation of relativistic quantum mechanics, and it is the basis of many quantum algorithms. We investigate how it searches the complete bipartite graph of $N$ vertices for one of $k$…

Quantum Physics · Physics 2019-03-04 Mason L. Rhodes , Thomas G. Wong

We propose a new method for designing quantum search algorithms for finding a "marked" element in the state space of a classical Markov chain. The algorithm is based on a quantum walk \'a la Szegedy (2004) that is defined in terms of the…

Quantum Physics · Physics 2018-03-22 Frédéric Magniez , Ashwin Nayak , Jérémie Roland , Miklos Santha

We use the abstract search algorithm and its extension due to Tulsi to analyze a spatial quantum search algorithm that finds a marked vertex in Hanoi networks of degree 4 faster than classical algorithms. We also analyze the effect of using…

Quantum Physics · Physics 2018-07-06 Franklin L. Marquezino , Renato Portugal , Stefan Boettcher

We construct a quantum random walk algorithm, based on the Dirac operator instead of the Laplacian. The algorithm explores multiple evolutionary branches by superposition of states, and does not require the coin toss instruction of…

Quantum Physics · Physics 2007-05-23 Apoorva Patel , K. S. Raghunathan , Pranaw Rungta

We present a novel methodological framework for quantum spatial search, generalising the Childs & Goldstone ($\mathcal{CG}$) algorithm via alternating applications of marked-vertex phase shifts and continuous-time quantum walks. We…

Quantum Physics · Physics 2021-09-30 S. Marsh , J. B. Wang

Although strongly regular graphs and the hypercube are not complete, they are "sufficiently complete" such that a randomly walking quantum particle asymptotically searches on them in the same $\Theta(\sqrt{N})$ time as on the complete…

Quantum Physics · Physics 2015-02-24 David A. Meyer , Thomas G. Wong

The paper considers the problem of finding a given substring in a text. It is known that the complexity of a classical search query in an unordered database is linear in the length of the text and a given substring. At the same time,…

Quantum Physics · Physics 2023-11-03 Farid Ablayev , Marat Ablayev , Nailya Salikhova

A quantum algorithm is a set of instructions for a quantum computer, however, unlike algorithms in classical computer science their results cannot be guaranteed. Quantum search algorithm can be described as the rotation of state vectors in…

Quantum Physics · Physics 2021-12-30 Bikramaditya Das , Kamal Gurnani , Bikash K. Behera , Prasanta K. Panigrahi

We study the problem of learning an unknown graph provided via an oracle using a quantum algorithm. We consider three query models. In the first model ("OR queries"), the oracle returns whether a given subset of the vertices contains any…

Quantum Physics · Physics 2021-01-26 Ashley Montanaro , Changpeng Shao

We present an adiabatic quantum algorithm for the abstract problem of searching marked vertices in a graph, or spatial search. Given a random walk (or Markov chain) $P$ on a graph with a set of unknown marked vertices, one can define a…

Quantum Physics · Physics 2010-09-08 Hari Krovi , Maris Ozols , Jérémie Roland

We introduce a structured quantum search algorithm that leverages entanglement maps and a fixed-point method to minimize oracle query complexity in unsorted datasets. By partitioning qubits into rows based on their entanglement order, the…

Quantum Physics · Physics 2025-07-22 Yash Prabhat , Snigdha Thakur , Ankur Raina

With the constant flow of data from vast sources over the past decades, a plethora of advanced analytical techniques have been developed to extract relevant information from different data types ranging from labeled data, quasi-labeled…

Quantum Physics · Physics 2025-11-07 Andrew Vlasic , Anh Pham

Grover's quantum search algorithm provides a way to speed up combinatorial search, but is not directly applicable to searching a physical database. Nevertheless, Aaronson and Ambainis showed that a database of N items laid out in d spatial…

Quantum Physics · Physics 2007-05-23 Andrew M. Childs , Jeffrey Goldstone

The Quantum Approximate Optimization Algorithm can naturally be applied to combinatorial search problems on graphs. The quantum circuit has p applications of a unitary operator that respects the locality of the graph. On a graph with…

Quantum Physics · Physics 2020-04-21 Edward Farhi , David Gamarnik , Sam Gutmann

We mainly study exceptional configuration for coined quantum walk search. For searching on a two-dimensional grid by AKR algorithm, we find some new classes of exceptional configurations that cannot be found by the AKR algorithm effectively…

Quantum Physics · Physics 2021-02-03 Meng Li , Yun Shang

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 search algorithms offer a remarkable advantage of quadratic reduction in query complexity using quantum superposition principle. However, how an actual architecture may access and handle the database in a quantum superposed state…

Quantum Physics · Physics 2023-11-06 Jung Jun Park , Kyunghyun Baek , M. S. Kim , Hyunchul Nha , Jaewan Kim , Jeongho Bang