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Related papers: Realization of a General Three-Qubit Quantum Gate

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Modern platforms for potential qubit candidates, such as trapped ions or neutral atoms, allow long range connectivity between distant physical qubits through shuttling. This opens up an avenue for transversal logical CNOT gates between…

Quantum Physics · Physics 2025-04-14 Kwok Ho Wan , Mark Webber , Austin G. Fowler , Winfried K. Hensinger

Quantum-circuit optimization is essential for any practical realization of quantum computation, in order to beat decoherence. We present a scheme for implementing the final stage in the compilation of quantum circuits, i.e., for finding the…

Quantum Physics · Physics 2007-05-23 Juha J. Vartiainen , Antti O. Niskanen , Mikio Nakahara , Martti M. Salomaa

There are well-known protocols for performing CNOT quantum logic with qubits coupled by particular high-symmetry (Ising or Heisenberg) interactions. However, many architectures being considered for quantum computation involve qubits or…

Quantum Physics · Physics 2015-05-13 Michael R. Geller , Emily J. Pritchett , Andrei Galiautdinov , John M. Martinis

We propose a scheme for implementing the CNOT gate over qubits encoded in a pair of electron spins in a double quantum dot. The scheme is based on exchange and spin orbit interactions and on local gradients in Zeeman fields. We find that…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Jelena Klinovaja , Dimitrije Stepanenko , Bertrand I. Halperin , Daniel Loss

We study in detail the algebraic structures underlying quantum circuits generated by CNOT gates. Our results allow us to propose polynomial-time heuristics to reduce the number of gates used in a given CNOT circuit and we also give…

Quantum Physics · Physics 2020-12-18 Marc Bataille

Spin qubits in semiconductor quantum dots are a promising platform for quantum computing, however scaling to large systems is hampered by crosstalk and charge noise. Crosstalk here refers to the unwanted off-resonant rotation of idle qubits…

Mesoscale and Nanoscale Physics · Physics 2024-05-17 David W. Kanaar , J. P. Kestner

From a geometric approach, we derive the minimum number of applications needed for an arbitrary Controlled-Unitary gate to construct a universal quantum circuit. A new analytic construction procedure is presented and shown to be either…

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

The work proposes an extension of the quantum circuit formalism where qubits (wires) are circular instead of linear. The left-to-right interpretation of a quantum circuit is replaced by a circular representation which allows to select the…

Quantum Physics · Physics 2016-04-12 Alexandru Paler

Numerical optimization is used to design linear-optical devices that implement a desired quantum gate with perfect fidelity, while maximizing the success rate. For the 2-qubit CS (or CNOT) gate, we provide numerical evidence that the…

Quantum Physics · Physics 2015-05-13 Dmitry B. Uskov , Lev Kaplan , A. Matthew Smith , Sean D. Huver , Jonathan P. Dowling

One of the main advantages of an optical approach to quantum computing is the fact that optical fibers can be used to connect the logic and memory devices to form useful circuits, in analogy with the wires of a conventional computer. Here…

Quantum Physics · Physics 2016-09-08 T. B. Pittman , B. C Jacobs , J. D. Franson

Quantum computation is traditionally expressed in terms of quantum bits, or qubits. In this work, we instead consider three-level qu$trits$. Past work with qutrits has demonstrated only constant factor improvements, owing to the $\log_2(3)$…

Single qubit rotation gate and the controlled-NOT (CNOT) gate constitute a complete set of gates for universal quantum computation. In general the CNOT gate are only for two nearby qubits. For two qubits which are remote from each other, we…

Quantum Physics · Physics 2009-09-29 Gui-Fang Dang , Heng Fan

We develop a systematic method of performing corrected gate operations on an array of exchange-coupled singlet-triplet qubits in the presence of both fluctuating nuclear Overhauser field gradients and charge noise. The single-qubit control…

Quantum Physics · Physics 2013-04-12 J. P. Kestner , Xin Wang , Lev S. Bishop , Edwin Barnes , S. Das Sarma

The controlled-NOT gate and controlled square-root NOT gate play an important role in quantum algorithm. This article reports the experimental results of these two universal quantum logic gates (controlled square-root NOT gate and…

Quantum Physics · Physics 2007-05-23 Daxiu Wei , Xiaodong Yang , Jun Luo , Xianping Sun , Xizhi Zeng , Maili Liu , Shangwu Ding

Scalable and fault-tolerant quantum computation will require error correction. This will demand constant measurement of many-qubit observables, implemented using a vast number of CNOT gates. Indeed, practically all operations performed by a…

Quantum Physics · Physics 2018-10-16 Andreas Peter , Daniel Loss , James R. Wootton

A number of quantum algorithms have been performed on small quantum computers; these include Shor's prime factorization algorithm, error correction, Grover's search algorithm and a number of analog and digital quantum simulations. Because…

Quantum Physics · Physics 2012-08-28 Andrew T. Sornborger

Implementation of high-dimensional (HD) quantum gates shows very promising perspectives for HD quantum computation. A bipartite quantum system with arbitrary dimensions $n$ and $m$ is termed a quNit-quMit. Here we propose a synthesis scheme…

Quantum Physics · Physics 2026-04-14 Gui-Long Jiang , Hai-Rui Wei

We present a scalable set of universal gates and multiply controlled gates in a qudit basis through a bijective mapping from N qubits to qudits with D = 2^N levels via rotations in U(2). For each of the universal gates (H, CNOT, and T), as…

Quantum Physics · Physics 2022-06-16 Pamela Rambow , Mingzhen Tian

Quantum algorithms often benefit from the ability to execute multi-qubit (>2) gates. To date such multi-qubit gates are typically decomposed into single- and two-qubit gates, particularly in superconducting qubit architectures. The ability…

Optimal implementation of quantum gates is crucial for designing a quantum computer. We consider the matrix representation of an arbitrary multiqubit gate. By ordering the basis vectors using the Gray code, we construct the quantum circuit…

Quantum Physics · Physics 2007-05-23 Juha J. Vartiainen , Mikko Mottonen , Martti M. Salomaa