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Related papers: Replacing Two Controlled-U's with Two CNOTs

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Unitary decomposition is a widely used method to map quantum algorithms to an arbitrary set of quantum gates. Efficient implementation of this decomposition allows for translation of bigger unitary gates into elementary quantum operations,…

Quantum Physics · Physics 2024-03-14 A. M. Krol , A. Sarkar , I. Ashraf , Z. Al-Ars , K. Bertels

Single qubit rotations and two-qubit CNOT operations are crucial ingredients for universal quantum computing. While high fidelity single qubit operations have been achieved using the electron spin degree of freedom, realizing a robust CNOT…

Quantum Physics · Physics 2018-02-02 D. M. Zajac , A. J. Sigillito , M. Russ , F. Borjans , J. M. Taylor , G. Burkard , J. R. Petta

We introduce a complete transformation rule set and a minimal equation set for controlled-NOT (CNOT)-based quantum circuits. Using these rules, quantum circuits that compute the same Boolean function are reduced to the same normal form. We…

Quantum Physics · Physics 2013-05-08 Issei Sakashita

Simpler encoding and decoding networks are necessary for more reliable quantum error correcting codes (QECCs). The simplification of the encoder-decoder circuit for a perfect five-qubit QECC can be derived analytically if the QECC is…

Quantum Physics · Physics 2007-05-23 Jin-Yuan Hsieh , Che-Ming Li , Der-San Chuu

The three-input TOFFOLI gate is the workhorse of circuit synthesis for classical logic operations on quantum data, e.g., reversible arithmetic circuits. In physical implementations, however, TOFFOLI gates are decomposed into six CNOT gates…

Quantum Physics · Physics 2011-11-03 Vivek V. Shende , Igor L. Markov

Quantum circuit model is the most popular paradigm for implementing complex quantum computation. Based on Cartan decomposition, we show that $2(N-1)$ generalized controlled-$X$ (GCX) gates, $6$ single-qubit rotations about the $y$- and…

Quantum Physics · Physics 2022-09-13 Gui-Long Jiang , Hai-Rui Wei , Guo-Zhu Song , Ming Hua

We show that any unitary operator on the $d_A\times d_B$ system ($d_A\ge 2$) can be decomposed into the product of at most $4d_A-5$ controlled unitary operators. The number can be reduced to $2d_A-1$ when $d_A$ is a power of two. We also…

Quantum Physics · Physics 2015-03-19 Lin Chen , Li Yu

We construct optimized implementations of the CNOT and other universal two-qubit gates that, unlike many of the previously proposed protocols, are carried out in a single step. The new protocols require tunable inter-qubit couplings but, in…

Quantum Physics · Physics 2013-05-29 I. A. Grigorenko , D. V. Khveshchenko

We show that two electrons confined in a square semiconductor quantum dot have two isolated low-lying energy eigenstates, which have the potential to form the basis of scalable computing elements (qubits). Initialisation, one-qubit and…

Quantum Physics · Physics 2009-11-07 J. H. Jefferson , M. Fearn , D. L. J. Tipton , T. P. Spiller

We investigate the topological quantum compilation of two-qubit operations within a system of Fibonacci anyons. Our primary goal is to generate gates that are approximately leakage-free and equivalent to the controlled-NOT (CNOT) gate up to…

Quantum Physics · Physics 2024-11-26 Phillip C. Burke , Christos Aravanis , Johannes Aspman , Jakub Mareček , Jiří Vala

The physical limitations of quantum hardware often require nearest-neighbor qubit structures, in which two-qubit gates are required to construct nearest-neighbor quantum circuits. However, two-qubit gates are considered a major cost of…

Quantum Physics · Physics 2022-08-31 Byeongyong Park , Doyeol Ahn

Two-qubit quantum gates play an essential role in quantum computing, whose operation critically depends on the entanglement between two qubits. Resonantly driven controlled-NOT (CNOT) gates based on silicon double quantum dots (DQDs) are…

Mesoscale and Nanoscale Physics · Physics 2018-09-11 Tong Wu , Jing Guo

How to implement a computation task efficiently is the central problem in quantum computation science. For a quantum circuit, the multi-control unitary operations are the very important components. We present an extremely efficient approach…

Quantum Physics · Physics 2019-01-29 Qing Lin

Optimal construction of quantum operations is a fundamental problem in the realization of quantum computation. We here introduce a newly discovered quantum gate, B, that can implement any arbitrary two-qubit quantum operation with minimal…

Quantum Physics · Physics 2009-11-10 Jun Zhang , Jiri Vala , Shankar Sastry , K. Birgitta Whaley

Unitary quantum gates constitute the building blocks of Quantum Computing in the circuit paradigm. In this work, we engineer a locally driven two-qubit Hamiltonian whose instantaneous ground-state dynamics generates the controlled-NOT…

Double-dot exchange-only qubit represents a promising compromise between high speed and simple fabrication in solid-state implementations. A couple of interacting double-dot exchange-only qubits, each composed by three electrons distributed…

Quantum Physics · Physics 2018-09-05 E. Ferraro , M. De Michielis , M. Fanciulli , E. Prati

Uniformly controlled one-qubit gates are quantum gates which can be represented as direct sums of two-dimensional unitary operators acting on a single qubit. We present a quantum gate array which implements any n-qubit gate of this type…

Quantum Physics · Physics 2009-11-10 Ville Bergholm , Juha J. Vartiainen , Mikko Mottonen , Martti M. Salomaa

We develop a new symbolic-numeric algorithm for the certification of singular isolated points, using their associated local ring structure and certified numerical computations. An improvement of an existing method to compute inverse systems…

Symbolic Computation · Computer Science 2011-01-18 Angelos Mantzaflaris , Bernard Mourrain

Checking whether two quantum circuits are approximately equivalent is a common task in quantum computing. We consider a closely related identity check problem: given a quantum circuit $U$, one has to estimate the diamond-norm distance…

Quantum Physics · Physics 2024-01-31 Sergey Bravyi , Natalie Parham , Minh Tran

The use of a few intermediate qutrits for efficient decomposition of 3-qubit unitary gates has been proposed, to obtain an exponential reduction in the depth of the decomposed circuit. An intermediate qutrit implies that a qubit is operated…

Quantum Physics · Physics 2023-09-13 Ritajit Majumdar , Amit Saha , Amlan Chakrabarti , Susmita Sur-Kolay