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Related papers: Some Notes on Parallel Quantum Computation

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In quantum computing the decoherence time of the qubits determines the computation time available and this time is very limited when using current hardware. In this paper we minimize the execution time (the depth) for a class of circuits…

Parallelization is a major challenge in quantum algorithms due to physical constraints like no-cloning. This is vividly illustrated by the conjecture of Moore and Nilsson from their seminal work on quantum circuit complexity [MN01,…

Quantum Physics · Physics 2025-10-07 Adam Bene Watts , Charles R. Chen , J. William Helton , Joseph Slote

In this paper, we investigate how quantum architectures affect the efficiency of the execution of the quantum Fourier transform (QFT) and linear transformations, which are essential parts of the stabilizer/Clifford group circuits. In…

Quantum Physics · Physics 2007-11-15 D. Maslov

We study the implementation of quantum channels with quantum computers while minimizing the experimental cost, measured in terms of the number of Controlled-NOT (C-NOT) gates required (single-qubit gates are free). We consider three…

Quantum Physics · Physics 2017-05-17 Raban Iten , Roger Colbeck , Matthias Christandl

The circuit model of a quantum computer consists of sequences of gate operations between quantum bits (qubits), drawn from a universal family of discrete operations. The ability to execute parallel entangling quantum gates offers clear…

Quantum Physics · Physics 2021-11-19 C. Figgatt , A. Ostrander , N. M. Linke , K. A. Landsman , D. Zhu , D. Maslov , C. Monroe

In the paper, we consider quantum circuits for the Quantum Fourier Transform (QFT) algorithm. The QFT algorithm is a very popular technique used in many quantum algorithms. We present a generic method for constructing quantum circuits for…

Quantum Physics · Physics 2026-01-05 Kamil Khadiev , Aliya Khadieva , Vadim Sagitov , Kamil Khasanov

The rapid evolution of quantum devices fuels concerted efforts to experimentally establish quantum advantage over classical computing. Many demonstrations of quantum advantage, however, rely on computational assumptions and face…

This paper initiates the study of quantum computing within the constraints of using a polylogarithmic ($O(\log^k n), k\geq 1$) number of qubits and a polylogarithmic number of computation steps. The current research in the literature has…

Quantum Physics · Physics 2007-05-23 Sanjay Gupta , R. K. P. Zia

Quantum computers are on the brink of surpassing the capabilities of even the most powerful classical computers. This naturally raises the question of how one can trust the results of a quantum computer when they cannot be compared to…

Recent years have seen rapid development in the subject of quantum coding theory, with breakthroughs on many exciting classes of codes, including quantum LDPC codes, quantum locally testable codes, and quantum codes with interesting…

Quantum Physics · Physics 2026-03-06 Adam Wills , Ting-Chun Lin , Rachel Yun Zhang , Min-Hsiu Hsieh

In the paper, we consider quantum circuits for Quantum fingerprinting (quantum hashing) and quantum Fourier transform (QFT) algorithms. Quantum fingerprinting (quantum hashing) is a well-known technique for comparing large objects using…

Quantum Physics · Physics 2026-02-04 Kamil Khadiev , Aliya Khadieva , Zeyu Chen , Junde Wu

A clever choice and design of gate sets can reduce the depth of a quantum circuit, and can improve the quality of the solution one obtains from a quantum algorithm. This is especially important for near-term quantum computers that suffer…

Quantum Physics · Physics 2025-07-08 Madhav Mohan , Julius de Hond , Servaas Kokkelmans

It is shown that a quantum controlled-NOT gate simultaneously performs the logical functions of three distinct conditional local operations. Each of these local operations can be verified by measuring a corresponding truth table of four…

Quantum Physics · Physics 2009-11-10 Holger F. Hofmann

Quantum circuit synthesis is the process in which an arbitrary unitary operation is decomposed into a sequence of gates from a universal set, typically one which a quantum computer can implement both efficiently and fault-tolerantly. As…

Quantum Physics · Physics 2016-10-17 Olivia Di Matteo , Michele Mosca

The efficient decomposition of multi-controlled gates is a significant factor in quantum compiling, both in circuit depth and T-gate count. Recent work has demonstrated that qudits have the potential to reduce resource requirements from…

Quantum Physics · Physics 2023-02-09 Michael Hanks , M. S. Kim

In this work we explore a correspondence between quantum circuits and low-degree polynomials over the finite field F_2. Any quantum circuit made up of Hadamard, Z, controlled-Z and controlled-controlled-Z gates gives rise to a degree-3…

Quantum Physics · Physics 2017-02-01 Ashley Montanaro

Quantum algorithm design usually assumes access to a perfect quantum computer with ideal properties like full connectivity, noise-freedom and arbitrarily long coherence time. In Noisy Intermediate-Scale Quantum (NISQ) devices, however, the…

Quantum Physics · Physics 2020-09-11 Xiangzhen Zhou , Sanjiang Li , Yuan Feng

The relevance of shallow-depth quantum circuits has recently increased, mainly due to their applicability to near-term devices. In this context, one of the main goals of quantum circuit complexity is to find problems that can be solved by…

Quantum Physics · Physics 2026-03-12 Alex Bredariol Grilo , Elham Kashefi , Damian Markham , Michael de Oliveira

We give a comprehensive characterization of the computational power of shallow quantum circuits combined with classical computation. Specifically, for classes of search problems, we show that the following statements hold, relative to a…

The depth of quantum circuits is a critical factor when running them on state-of-the-art quantum devices due to their limited coherence times. Reducing circuit depth decreases noise in near-term quantum computations and reduces overall…

Quantum Physics · Physics 2025-05-08 Elisa Bäumer , Stefan Woerner