English
Related papers

Related papers: Finding a marked node on any graph by continuous-t…

200 papers

Continuous-time quantum walks provide a natural framework to tackle the fundamental problem of finding a node among a set of marked nodes in a graph, known as spatial search. Whether spatial search by continuous-time quantum walk provides a…

Quantum Physics · Physics 2022-10-24 Simon Apers , Shantanav Chakraborty , Leonardo Novo , Jérémie Roland

In quantum computing, the quantum walk search algorithm is designed for locating fixed marked nodes within a graph. However, when multiple marked nodes exist, the conventional search algorithm lacks the capacity to simultaneously amplify…

Quantum Physics · Physics 2024-02-06 Himanshu Sahu , Kallol Sen

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

In this paper we define new Monte Carlo type classical and quantum hitting times, and we prove several relationships among these and the already existing Las Vegas type definitions. In particular, we show that for some marked state the two…

Quantum Physics · Physics 2018-03-22 Frederic Magniez , Ashwin Nayak , Peter C. Richter , Miklos Santha

The quantum-walk-based spatial search problem aims to find a marked vertex using a quantum walk on a graph with marked vertices. We describe a framework for determining the computational complexity of spatial search by continuous-time…

Quantum Physics · Physics 2024-12-25 Pedro H. G. Lugão , Renato Portugal , Mohamed Sabri , Hajime Tanaka

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

One of the most important algorithmic applications of quantum walks is to solve spatial search problems. A widely used quantum algorithm for this problem, introduced by Childs and Goldstone [Phys. Rev. A 70, 022314 (2004)], finds a marked…

Quantum Physics · Physics 2020-09-23 Shantanav Chakraborty , Leonardo Novo , Jérémie Roland

We give a quantum algorithm for finding a marked element on the grid when there are multiple marked elements. Our algorithm uses quadratically fewer steps than a random walk on the grid, ignoring logarithmic factors. This is the first known…

Quantum Physics · Physics 2017-07-04 Peter Hoyer , Mojtaba Komeili

A quantum walk algorithm can detect the presence of a marked vertex on a graph quadratically faster than the corresponding random walk algorithm (Szegedy, FOCS 2004). However, quantum algorithms that actually find a marked element…

Quantum Physics · Physics 2019-03-19 Andris Ambainis , András Gilyén , Stacey Jeffery , Martins Kokainis

Spatial search is an important problem in quantum computation, which aims to find a marked vertex on a graph. We propose a novel approach for designing deterministic quantum search algorithms on a variety of graphs via alternating quantum…

Quantum Physics · Physics 2023-08-25 Qingwen Wang , Ying Jiang , Shiguang Feng , Lvzhou Li

In the typical spatial search problems solved by continuous-time quantum walk, changing the location of the marked vertices does not alter the search problem. In this paper, we consider search when this is no longer true. In particular, we…

Quantum Physics · Physics 2016-04-11 Thomas G. Wong

To investigate the performance of quantum information tasks on networks whose topology changes in time, we study the spatial search algorithm by continuous time quantum walk to find a marked node on a random temporal network. We consider a…

Quantum Physics · Physics 2017-11-30 Shantanav Chakraborty , Leonardo Novo , Serena Di Giorgio , Yasser Omar

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

Quantum walk is a potent technique for building quantum algorithms. This paper examines the quantum walk search algorithm on complete multipartite graphs with multiple marked vertices, which has not been explored before. Two specific cases…

Quantum Physics · Physics 2024-10-08 Ningxiang Chen , Meng Li , Xiaoming Sun

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

The scale-free property emerges in various real-world networks and is an essential property which characterizes the dynamics or features of such networks. In this work we investigate the effect of this scale-free property on a quantum…

Quantum Physics · Physics 2020-02-12 Tomo Osada , Bruno Coutinho , Yasser Omar , Kaoru Sanaka , William J. Munro , Kae Nemoto

The problem of finding a marked node in a graph can be solved by the spatial search algorithm based on continuous-time quantum walks (CTQW). However, this algorithm is known to run in optimal time only for a handful of graphs. In this work,…

Quantum Physics · Physics 2016-03-23 Shantanav Chakraborty , Leonardo Novo , Andris Ambainis , Yasser Omar

This work examines the time complexity of quantum search algorithms on combinatorial $t$-designs with multiple marked elements using the continuous-time quantum walk. Through a detailed exploration of $t$-designs and their incidence…

Quantum Physics · Physics 2025-04-08 Pedro H. G. Lugão , Renato Portugal

We solve an open problem by constructing quantum walks that not only detect but also find marked vertices in a graph. In the case when the marked set $M$ consists of a single vertex, the number of steps of the quantum walk is quadratically…

Quantum Physics · Physics 2016-03-01 Hari Krovi , Frédéric Magniez , Maris Ozols , Jérémie Roland

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
‹ Prev 1 2 3 10 Next ›