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Related papers: Demonstration of a quantum nondemolition sum gate

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We develop an architecture of hybrid quantum solid-state processing unit for universal quantum computing. The architecture allows distant and nonidentical solid-state qubits in distinct physical systems to interact and work collaboratively.…

Quantum Physics · Physics 2012-05-08 Pei Pei , Feng-Yang Zhang , Chong Li , He-Shan Song

Quantum computers are the ideal platform for quantum simulations. Given enough coherent operations and qubits, such machines can be leveraged to simulate strongly correlated materials, where intricate quantum effects give rise to…

Quantum Physics · Physics 2016-12-14 Pierre-Luc Dallaire-Demers , Frank K. Wilhelm

The problems related to the management of large quantum registers could be handled in the context of distributed quantum computation: unitary non-local transformations among spatially separated local processors are realized performing local…

Quantum Physics · Physics 2015-06-26 M. Paternostro , M. S. Kim , G. M. Palma

Fault-tolerant logic gates will consume a large proportion of the resources of a two-dimensional quantum computing architecture. Here we show how to perform a fault-tolerant non-Clifford gate with the surface code; a quantum…

Quantum Physics · Physics 2021-04-20 Benjamin J. Brown

The Zeno effect, in which repeated observation freezes the dynamics of a quantum system, stands as an iconic oddity of quantum mechanics. When a measurement is unable to distinguish between states in a subspace, the dynamics within that…

We demonstrate that in a coupled two-qubit system any single-qubit gate can be decomposed into two conditional two-qubit gates and that any conditional two-qubit gate can be implemented by a manipulation analogous to that used for a…

Quantum Physics · Physics 2009-11-11 Zhongyuan Zhou , Shih-I Chu , Siyuan Han

Robust quantum computation with d-level quantum systems (qudits) poses two requirements: fast, parallel quantum gates and high fidelity two-qudit gates. We first describe how to implement parallel single qudit operations. It is by now well…

Quantum Physics · Physics 2009-11-13 Dianne P. O'Leary , Gavin K. Brennen , Stephen S. Bullock

We present a universal quantum computing architecture which combines the measurement-driven aspect of MBQC with the circuit model's algorithm dependent generation of qubit entanglement. Our architecture, which we call QGATE, is tailored for…

Quantum Physics · Physics 2026-03-20 Samuel J. Sheldon , Pieter Kok , Callum W. Duncan

We consider light scattering from ultracold atoms trapped in an optical lattice into a cavity. The measurement of photons leaking out the cavity provides a quantum nondemolition (QND) access to various atomic variables. Depending on the…

Quantum Physics · Physics 2009-04-29 Igor B. Mekhov , Helmut Ritsch

We study brick wall quantum circuits enjoying a global fermionic symmetry. The constituent 2-qubit gate, and its fermionic symmetry, derive from a 2-particle scattering matrix in integrable, supersymmetric quantum field theory in 1+1…

Quantum Physics · Physics 2024-09-25 Pietro Richelli , Kareljan Schoutens , Alberto Zorzato

Quantum homomorphic encryption integrates quantum computing with homomorphic encryption, which allows calculations to be performed directly on encrypted data without decryption on the server side. In this paper, we explore distributed…

Quantum Physics · Physics 2025-02-27 Haoyun Zhang , Yu-Ting Lei , Xing-bo Pan

A problem of universality in simulation of evolution of quantum system and in theory of quantum computations is related with the possibility of expression or approximation of arbitrary unitary transformation by composition of specific…

Quantum Physics · Physics 2009-11-06 Alexander Yu. Vlasov

In the circuit model, quantum computers rely on the availability of a universal quantum gate set. A particularly intriguing example is a set of two-qubit only gates: matchgates, along with SWAP (the exchange of two qubits). In this paper,…

Quantum Physics · Physics 2011-03-04 S. Ramelow , A. Fedrizzi , A. M. Steinberg , A. G. White

An investigation of an optimal universal unitary Controlled-NOT gate that performs a specific operation on two unknown states of qubits taken from a great circle of the Bloch sphere is presented. The deep analogy between the optimal…

Quantum Physics · Physics 2010-11-02 Michael Siomau , Stephan Fritzsche

An implementation of a universal solid-state quantum register based on electron space states in field-defined double quantum dots (DQD possesses one electron in two adjacent tunnel bound dots) in an ultrathin semiconductor nanowire is…

Mesoscale and Nanoscale Physics · Physics 2025-07-14 Vladimir Vyurkov , Leonid Fedichkin , Igor Semenikhin , Denis Drozhzhin , Konstantin Rudenko , Vladimir Lukichev

We report the characterization of a universal set of logic gates for one-way quantum computing using a four-photon `star' cluster state generated by fusing photons from two independent photonic crystal fibre sources. We obtain a fidelity…

Quantum Physics · Physics 2013-12-25 B. A. Bell , M. S. Tame , A. S. Clark , R. W. Nock , W. J. Wadsworth , J. G. Rarity

Quantum computation provides great speedup over its classical counterpart for certain problems. One of the key challenges for quantum computation is to realize precise control of the quantum system in the presence of noise. Control of the…

Quantum Physics · Physics 2015-11-30 Xing Rong , Jianpei Geng , Fazhan Shi , Ying Liu , Kebiao Xu , Wenchao Ma , Fei Kong , Zhen Jiang , Yang Wu , Jiangfeng Du

In the scheme of a quantum nondemolition (QND) measurement, an observable is measured without perturbing its evolution. In the context of studies of decoherence in quantum computing, we examine the `open' quantum system of a two-level atom,…

Quantum Physics · Physics 2007-05-23 Subhashish Banerjee , R. Ghosh

We give a quantum gate construction - composed entirely from incidents of the CNOT gate - that generalises the qubit SWAP gate to higher dimensions. This new construction is more regular than and is an improvement on the WilNOT quantum gate…

Quantum Physics · Physics 2008-11-13 Colin Wilmott , Peter Wild

Two-level system fluctuators in superconducting devices have demonstrated coherent coupling with superconducting qubits. Here, we show that universal quantum logic gates can be realized in these two-level systems solely by tuning a…

Quantum Physics · Physics 2009-11-13 L. Tian , K. Jacobs